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README.md
54
README.md
@ -1,56 +1,52 @@
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# meanas
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# fdfd_tools
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**meanas** is a python package for electromagnetic simulations
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** DEPRECATED **
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This package is intended for building simulation inputs, analyzing
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simulation outputs, and running short simulations on unspecialized hardware.
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It is designed to provide tooling and a baseline for other, high-performance
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purpose- and hardware-specific solvers.
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The functionality in this module is now provided by [meanas](https://mpxd.net/code/jan/meanas).
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-----------------------
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**fdfd_tools** is a python package containing utilities for
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creating and analyzing 2D and 3D finite-difference frequency-domain (FDFD)
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electromagnetic simulations.
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**Contents**
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- Finite difference frequency domain (FDFD)
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* Library of sparse matrices for representing the electromagnetic wave
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equation in 3D, as well as auxiliary matrices for conversion between fields
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* Waveguide mode operators
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* Waveguide mode eigensolver
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* Stretched-coordinate PML boundaries (SCPML)
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* Functional versions of most operators
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* Anisotropic media (limited to diagonal elements eps_xx, eps_yy, eps_zz, mu_xx, ...)
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* Arbitrary distributions of perfect electric and magnetic conductors (PEC / PMC)
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- Finite difference time domain (FDTD)
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* Basic Maxwell time-steps
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* Poynting vector and energy calculation
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* Convolutional PMLs
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* Library of sparse matrices for representing the electromagnetic wave
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equation in 3D, as well as auxiliary matrices for conversion between fields
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* Waveguide mode solver and waveguide mode operators
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* Stretched-coordinate PML boundaries (SCPML)
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* Functional versions of most operators
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* Anisotropic media (eps_xx, eps_yy, eps_zz, mu_xx, ...)
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* Arbitrary distributions of perfect electric and magnetic conductors (PEC / PMC)
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This package does *not* provide a fast matrix solver, though by default
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`meanas.fdfd.solvers.generic(...)` will call
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`scipy.sparse.linalg.qmr(...)` to perform a solve.
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For 2D FDFD problems this should be fine; likewise, the waveguide mode
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```fdfd_tools.solvers.generic(...)``` will call
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```scipy.sparse.linalg.qmr(...)``` to perform a solve.
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For 2D problems this should be fine; likewise, the waveguide mode
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solver uses scipy's eigenvalue solver, with reasonable results.
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For solving large (or 3D) FDFD problems, I recommend a GPU-based iterative
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solver, such as [opencl_fdfd](https://mpxd.net/code/jan/opencl_fdfd) or
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For solving large (or 3D) problems, I recommend a GPU-based iterative
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solver, such as [opencl_fdfd](https://mpxd.net/gogs/jan/opencl_fdfd) or
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those included in [MAGMA](http://icl.cs.utk.edu/magma/index.html)). Your
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solver will need the ability to solve complex symmetric (non-Hermitian)
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linear systems, ideally with double precision.
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## Installation
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**Requirements:**
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* python 3 (tests require 3.7)
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* python 3 (written and tested with 3.5)
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* numpy
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* scipy
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Install with pip, via git:
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```bash
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pip install git+https://mpxd.net/code/jan/meanas.git@release
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pip install git+https://mpxd.net/gogs/jan/fdfd_tools.git@release
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```
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## Use
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See `examples/` for some simple examples; you may need additional
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packages such as [gridlock](https://mpxd.net/code/jan/gridlock)
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See examples/test.py for some simple examples; you may need additional
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packages such as [gridlock](https://mpxd.net/gogs/jan/gridlock)
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to run the examples.
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@ -1,44 +1,12 @@
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import numpy, scipy, gridlock, meanas
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from meanas.fdfd import bloch
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import numpy, scipy, gridlock, fdfd_tools
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from fdfd_tools import bloch
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from numpy.linalg import norm
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import logging
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from pathlib import Path
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logging.basicConfig(level=logging.DEBUG)
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logger = logging.getLogger(__name__)
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WISDOM_FILEPATH = pathlib.Path.home() / '.local' / 'share' / 'pyfftw' / 'wisdom.pickle'
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def pyfftw_save_wisdom(path):
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path = pathlib.Path(path)
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try:
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import pyfftw
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import pickle
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except ImportError as e:
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pass
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path.parent.mkdir(parents=True, exist_ok=True)
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with open(path, 'wb') as f:
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pickle.dump(wisdom, f)
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def pyfftw_load_wisdom(path):
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path = pathlib.Path(path)
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try:
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import pyfftw
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import pickle
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except ImportError as e:
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pass
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try:
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with open(path, 'rb') as f:
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wisdom = pickle.load(f)
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pyfftw.import_wisdom(wisdom)
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except FileNotFoundError as e:
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pass
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logger.info('Drawing grid...')
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dx = 40
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x_period = 400
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y_period = z_period = 2000
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@ -62,13 +30,11 @@ g2.shifts = numpy.zeros((6,3))
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g2.grids = [numpy.zeros(g.shape) for _ in range(6)]
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epsilon = [g.grids[0],] * 3
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reciprocal_lattice = numpy.diag(1000/numpy.array([x_period, y_period, z_period])) #cols are vectors
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pyfftw_load_wisdom(WISDOM_FILEPATH)
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reciprocal_lattice = numpy.diag(1e6/numpy.array([x_period, y_period, z_period])) #cols are vectors
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#print('Finding k at 1550nm')
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#k, f = bloch.find_k(frequency=1000/1550,
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# tolerance=(1000 * (1/1550 - 1/1551)),
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#k, f = bloch.find_k(frequency=1/1550,
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# tolerance=(1/1550 - 1/1551),
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# direction=[1, 0, 0],
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# G_matrix=reciprocal_lattice,
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# epsilon=epsilon,
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@ -76,15 +42,15 @@ pyfftw_load_wisdom(WISDOM_FILEPATH)
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#
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#print("k={}, f={}, 1/f={}, k/f={}".format(k, f, 1/f, norm(reciprocal_lattice @ k) / f ))
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logger.info('Finding f at [0.25, 0, 0]')
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print('Finding f at [0.25, 0, 0]')
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for k0x in [.25]:
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k0 = numpy.array([k0x, 0, 0])
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kmag = norm(reciprocal_lattice @ k0)
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tolerance = (1000/1550) * 1e-4/1.5 # df = f * dn_eff / n
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tolerance = (1e6/1550) * 1e-4/1.5 # df = f * dn_eff / n
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logger.info('tolerance {}'.format(tolerance))
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n, v = bloch.eigsolve(4, k0, G_matrix=reciprocal_lattice, epsilon=epsilon, tolerance=tolerance**2)
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n, v = bloch.eigsolve(4, k0, G_matrix=reciprocal_lattice, epsilon=epsilon, tolerance=tolerance)
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v2e = bloch.hmn_2_exyz(k0, G_matrix=reciprocal_lattice, epsilon=epsilon)
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v2h = bloch.hmn_2_hxyz(k0, G_matrix=reciprocal_lattice, epsilon=epsilon)
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ki = bloch.generate_kmn(k0, reciprocal_lattice, g.shape)
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@ -100,4 +66,3 @@ for k0x in [.25]:
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n_eff = norm(reciprocal_lattice @ k0) / f
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print('kmag/f = n_eff = {} \n wl = {}\n'.format(n_eff, 1/f ))
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pyfftw_save_wisdom(WISDOM_FILEPATH)
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@ -1,90 +0,0 @@
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import importlib
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import numpy
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from numpy.linalg import norm
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from meanas import vec, unvec
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from meanas.fdfd import waveguide_mode, functional, scpml
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from meanas.fdfd.solvers import generic as generic_solver
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import gridlock
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from matplotlib import pyplot
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__author__ = 'Jan Petykiewicz'
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def test1(solver=generic_solver):
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dx = 20 # discretization (nm/cell)
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pml_thickness = 10 # (number of cells)
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wl = 1550 # Excitation wavelength
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omega = 2 * numpy.pi / wl
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# Device design parameters
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w = 800
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th = 220
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center = [0, 0, 0]
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r0 = 8e3
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# refractive indices
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n_wg = numpy.sqrt(12.6) # ~Si
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n_air = 1.0 # air
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# Half-dimensions of the simulation grid
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y_max = 1200
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z_max = 900
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xyz_max = numpy.array([800, y_max, z_max]) + (pml_thickness + 2) * dx
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# Coordinates of the edges of the cells.
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half_edge_coords = [numpy.arange(dx/2, m + dx/2, step=dx) for m in xyz_max]
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edge_coords = [numpy.hstack((-h[::-1], h)) for h in half_edge_coords]
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edge_coords[0] = numpy.array([-dx, dx])
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# #### Create the grid and draw the device ####
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grid = gridlock.Grid(edge_coords, initial=n_air**2, num_grids=3)
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grid.draw_cuboid(center=center, dimensions=[8e3, w, th], eps=n_wg**2)
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dxes = [grid.dxyz, grid.autoshifted_dxyz()]
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for a in (1, 2):
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for p in (-1, 1):
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dxes = scmpl.stretch_with_scpml(dxes, omega=omega, axis=a, polarity=p,
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thickness=pml_thickness)
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wg_args = {
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'omega': omega,
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'dxes': [(d[1], d[2]) for d in dxes],
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'epsilon': vec(g.transpose([1, 2, 0]) for g in grid.grids),
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'r0': r0,
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}
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wg_results = waveguide_mode.solve_waveguide_mode_cylindrical(mode_number=0, **wg_args)
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E = wg_results['E']
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n_eff = wl / (2 * numpy.pi / wg_results['wavenumber'])
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print('n =', n_eff)
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print('alpha (um^-1) =', -4 * numpy.pi * numpy.imag(n_eff) / (wl * 1e-3))
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'''
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Plot results
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'''
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def pcolor(v):
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vmax = numpy.max(numpy.abs(v))
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pyplot.pcolor(v.T, cmap='seismic', vmin=-vmax, vmax=vmax)
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pyplot.axis('equal')
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pyplot.colorbar()
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pyplot.figure()
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pyplot.subplot(2, 2, 1)
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pcolor(numpy.real(E[0][:, :]))
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pyplot.subplot(2, 2, 2)
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pcolor(numpy.real(E[1][:, :]))
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pyplot.subplot(2, 2, 3)
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pcolor(numpy.real(E[2][:, :]))
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pyplot.subplot(2, 2, 4)
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pyplot.show()
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if __name__ == '__main__':
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test1()
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@ -2,10 +2,11 @@ import importlib
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import numpy
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from numpy.linalg import norm
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import meanas
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from meanas import vec, unvec, fdtd
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from meanas.fdfd import waveguide_mode, functional, scpml, operators
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from meanas.fdfd.solvers import generic as generic_solver
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from fdfd_tools import vec, unvec, waveguide_mode
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import fdfd_tools
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import fdfd_tools.functional
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import fdfd_tools.grid
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from fdfd_tools.solvers import generic as generic_solver
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import gridlock
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@ -56,23 +57,18 @@ def test0(solver=generic_solver):
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dxes = [grid.dxyz, grid.autoshifted_dxyz()]
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for a in (0, 1, 2):
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for p in (-1, 1):
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dxes = meanas.fdfd.scpml.stretch_with_scpml(dxes, axis=a, polarity=p, omega=omega,
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thickness=pml_thickness)
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dxes = fdfd_tools.grid.stretch_with_scpml(dxes, axis=a, polarity=p, omega=omega,
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thickness=pml_thickness)
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J = [numpy.zeros_like(grid.grids[0], dtype=complex) for _ in range(3)]
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J[1][15, grid.shape[1]//2, grid.shape[2]//2] = 1
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J[1][15, grid.shape[1]//2, grid.shape[2]//2] = 1e5
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'''
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Solve!
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'''
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sim_args = {
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'omega': omega,
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'dxes': dxes,
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'epsilon': vec(grid.grids),
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}
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x = solver(J=vec(J), **sim_args)
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A = operators.e_full(omega, dxes, vec(grid.grids)).tocsr()
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A = fdfd_tools.functional.e_full(omega, dxes, vec(grid.grids)).tocsr()
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b = -1j * omega * vec(J)
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print('Norm of the residual is ', norm(A @ x - b))
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@ -117,26 +113,24 @@ def test1(solver=generic_solver):
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dxes = [grid.dxyz, grid.autoshifted_dxyz()]
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for a in (0, 1, 2):
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for p in (-1, 1):
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dxes = scpml.stretch_with_scpml(dxes,omega=omega, axis=a, polarity=p,
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thickness=pml_thickness)
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dxes = fdfd_tools.grid.stretch_with_scpml(dxes,omega=omega, axis=a, polarity=p,
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thickness=pml_thickness)
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half_dims = numpy.array([10, 20, 15]) * dx
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dims = [-half_dims, half_dims]
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dims[1][0] = dims[0][0]
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ind_dims = (grid.pos2ind(dims[0], which_shifts=None).astype(int),
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grid.pos2ind(dims[1], which_shifts=None).astype(int))
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src_axis = 0
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wg_args = {
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'omega': omega,
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'slices': [slice(i, f+1) for i, f in zip(*ind_dims)],
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'dxes': dxes,
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'axis': src_axis,
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'axis': 0,
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'polarity': +1,
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'epsilon': grid.grids,
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}
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wg_results = waveguide_mode.solve_waveguide_mode(mode_number=0, **wg_args)
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J = waveguide_mode.compute_source(**wg_args, E=wg_results['E'], wavenumber=wg_results['wavenumber'])
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wg_results = waveguide_mode.solve_waveguide_mode(mode_number=0, **wg_args, epsilon=grid.grids)
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J = waveguide_mode.compute_source(**wg_args, **wg_results)
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H_overlap = waveguide_mode.compute_overlap_e(**wg_args, **wg_results)
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pecg = gridlock.Grid(edge_coords, initial=0.0, num_grids=3)
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@ -147,12 +141,6 @@ def test1(solver=generic_solver):
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# pmcg.draw_cuboid(center=[700, 0, 0], dimensions=[80, 1e8, 1e8], eps=1)
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# pmcg.visualize_isosurface()
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def pcolor(v):
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vmax = numpy.max(numpy.abs(v))
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pyplot.pcolor(v, cmap='seismic', vmin=-vmax, vmax=vmax)
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pyplot.axis('equal')
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pyplot.colorbar()
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'''
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Solve!
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'''
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@ -167,7 +155,7 @@ def test1(solver=generic_solver):
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x = solver(J=vec(J), **sim_args)
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b = -1j * omega * vec(J)
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A = operators.e_full(**sim_args).tocsr()
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A = fdfd_tools.operators.e_full(**sim_args).tocsr()
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print('Norm of the residual is ', norm(A @ x - b))
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E = unvec(x, grid.shape)
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@ -175,21 +163,27 @@ def test1(solver=generic_solver):
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'''
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Plot results
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'''
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def pcolor(v):
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vmax = numpy.max(numpy.abs(v))
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pyplot.pcolor(v, cmap='seismic', vmin=-vmax, vmax=vmax)
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pyplot.axis('equal')
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pyplot.colorbar()
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center = grid.pos2ind([0, 0, 0], None).astype(int)
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pyplot.figure()
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pyplot.subplot(2, 2, 1)
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pcolor(numpy.real(E[1][center[0], :, :]).T)
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pcolor(numpy.real(E[1][center[0], :, :]))
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pyplot.subplot(2, 2, 2)
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pyplot.plot(numpy.log10(numpy.abs(E[1][:, center[1], center[2]]) + 1e-10))
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pyplot.subplot(2, 2, 3)
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pcolor(numpy.real(E[1][:, :, center[2]]).T)
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pcolor(numpy.real(E[1][:, :, center[2]]))
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pyplot.subplot(2, 2, 4)
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def poyntings(E):
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e = vec(E)
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h = operators.e2h(omega, dxes) @ e
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cross1 = operators.poynting_e_cross(e, dxes) @ h.conj()
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cross2 = operators.poynting_h_cross(h.conj(), dxes) @ e
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h = fdfd_tools.operators.e2h(omega, dxes) @ e
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cross1 = fdfd_tools.operators.poynting_e_cross(e, dxes) @ h.conj()
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cross2 = fdfd_tools.operators.poynting_h_cross(h.conj(), dxes) @ e
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s1 = unvec(0.5 * numpy.real(cross1), grid.shape)
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s2 = unvec(0.5 * numpy.real(-cross2), grid.shape)
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return s1, s2
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@ -215,7 +209,7 @@ def module_available(name):
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if __name__ == '__main__':
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#test0()
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# test0()
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if module_available('opencl_fdfd'):
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from opencl_fdfd import cg_solver as opencl_solver
|
@ -10,7 +10,7 @@ import time
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import numpy
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import h5py
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from meanas import fdtd
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from fdfd_tools import fdtd
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from masque import Pattern, shapes
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import gridlock
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import pcgen
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25
fdfd_tools/__init__.py
Normal file
25
fdfd_tools/__init__.py
Normal file
@ -0,0 +1,25 @@
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"""
|
||||
Electromagnetic FDFD simulation tools
|
||||
|
||||
Tools for 3D and 2D Electromagnetic Finite Difference Frequency Domain (FDFD)
|
||||
simulations. These tools handle conversion of fields to/from vector form,
|
||||
creation of the wave operator matrix, stretched-coordinate PMLs, PECs and PMCs,
|
||||
field conversion operators, waveguide mode operator, and waveguide mode
|
||||
solver.
|
||||
|
||||
This package only contains a solver for the waveguide mode eigenproblem;
|
||||
if you want to solve 3D problems you can use your favorite iterative sparse
|
||||
matrix solver (so long as it can handle complex symmetric [non-Hermitian]
|
||||
matrices, ideally with double precision).
|
||||
|
||||
|
||||
Dependencies:
|
||||
- numpy
|
||||
- scipy
|
||||
|
||||
"""
|
||||
|
||||
from .vectorization import vec, unvec, field_t, vfield_t
|
||||
from .grid import dx_lists_t
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
@ -73,46 +73,21 @@ This module contains functions for generating and solving the
|
||||
|
||||
'''
|
||||
|
||||
from typing import Tuple, Callable
|
||||
from typing import List, Tuple, Callable, Dict
|
||||
import logging
|
||||
import numpy
|
||||
from numpy import pi, real, trace
|
||||
from numpy.fft import fftfreq
|
||||
from numpy.fft import fftn, ifftn, fftfreq
|
||||
import scipy
|
||||
import scipy.optimize
|
||||
from scipy.linalg import norm
|
||||
import scipy.sparse.linalg as spalg
|
||||
|
||||
from .eigensolvers import rayleigh_quotient_iteration
|
||||
from . import field_t
|
||||
|
||||
logger = logging.getLogger(__name__)
|
||||
|
||||
|
||||
try:
|
||||
import pyfftw.interfaces.numpy_fft
|
||||
import pyfftw.interfaces
|
||||
import multiprocessing
|
||||
logger.info('Using pyfftw')
|
||||
|
||||
pyfftw.interfaces.cache.enable()
|
||||
pyfftw.interfaces.cache.set_keepalive_time(3600)
|
||||
fftw_args = {
|
||||
'threads': multiprocessing.cpu_count(),
|
||||
'overwrite_input': True,
|
||||
'planner_effort': 'FFTW_EXHAUSTIVE',
|
||||
}
|
||||
|
||||
def fftn(*args, **kwargs):
|
||||
return pyfftw.interfaces.numpy_fft.fftn(*args, **kwargs, **fftw_args)
|
||||
|
||||
def ifftn(*args, **kwargs):
|
||||
return pyfftw.interfaces.numpy_fft.ifftn(*args, **kwargs, **fftw_args)
|
||||
|
||||
except ImportError:
|
||||
from numpy.fft import fftn, ifftn
|
||||
logger.info('Using numpy fft')
|
||||
|
||||
|
||||
def generate_kmn(k0: numpy.ndarray,
|
||||
G_matrix: numpy.ndarray,
|
||||
shape: numpy.ndarray
|
||||
@ -280,7 +255,7 @@ def hmn_2_hxyz(k0: numpy.ndarray,
|
||||
:return: Function for converting h_mn into H_xyz
|
||||
"""
|
||||
shape = epsilon[0].shape + (1,)
|
||||
_k_mag, m, n = generate_kmn(k0, G_matrix, shape)
|
||||
k_mag, m, n = generate_kmn(k0, G_matrix, shape)
|
||||
|
||||
def operator(h: numpy.ndarray):
|
||||
hin_m, hin_n = [hi.reshape(shape) for hi in numpy.split(h, 2)]
|
||||
@ -354,14 +329,147 @@ def inverse_maxwell_operator_approx(k0: numpy.ndarray,
|
||||
d_xyz = fftn(ifftn(e_xyz, axes=range(3)) * epsilon, axes=range(3))
|
||||
|
||||
# cross product and transform into mn basis crossinv_t2c
|
||||
h_m = numpy.sum(d_xyz * n, axis=3)[:, :, :, None] / +k_mag
|
||||
h_n = numpy.sum(d_xyz * m, axis=3)[:, :, :, None] / -k_mag
|
||||
h_m = numpy.sum(e_xyz * n, axis=3)[:, :, :, None] / +k_mag
|
||||
h_n = numpy.sum(e_xyz * m, axis=3)[:, :, :, None] / -k_mag
|
||||
|
||||
return numpy.hstack((h_m.ravel(), h_n.ravel()))
|
||||
|
||||
return operator
|
||||
|
||||
|
||||
def eigsolve(num_modes: int,
|
||||
k0: numpy.ndarray,
|
||||
G_matrix: numpy.ndarray,
|
||||
epsilon: field_t,
|
||||
mu: field_t = None,
|
||||
tolerance = 1e-8,
|
||||
) -> Tuple[numpy.ndarray, numpy.ndarray]:
|
||||
"""
|
||||
Find the first (lowest-frequency) num_modes eigenmodes with Bloch wavevector
|
||||
k0 of the specified structure.
|
||||
|
||||
:param k0: Bloch wavevector, [k0x, k0y, k0z].
|
||||
:param G_matrix: 3x3 matrix, with reciprocal lattice vectors as columns.
|
||||
:param epsilon: Dielectric constant distribution for the simulation.
|
||||
All fields are sampled at cell centers (i.e., NOT Yee-gridded)
|
||||
:param mu: Magnetic permability distribution for the simulation.
|
||||
Default None (1 everywhere).
|
||||
:return: (eigenvalues, eigenvectors) where eigenvalues[i] corresponds to the
|
||||
vector eigenvectors[i, :]
|
||||
"""
|
||||
h_size = 2 * epsilon[0].size
|
||||
|
||||
kmag = norm(G_matrix @ k0)
|
||||
|
||||
'''
|
||||
Generate the operators
|
||||
'''
|
||||
mop = maxwell_operator(k0=k0, G_matrix=G_matrix, epsilon=epsilon, mu=mu)
|
||||
imop = inverse_maxwell_operator_approx(k0=k0, G_matrix=G_matrix, epsilon=epsilon, mu=mu)
|
||||
|
||||
scipy_op = spalg.LinearOperator(dtype=complex, shape=(h_size, h_size), matvec=mop)
|
||||
scipy_iop = spalg.LinearOperator(dtype=complex, shape=(h_size, h_size), matvec=imop)
|
||||
|
||||
y_shape = (h_size, num_modes)
|
||||
|
||||
def rayleigh_quotient(Z: numpy.ndarray, approx_grad: bool = True):
|
||||
"""
|
||||
Absolute value of the block Rayleigh quotient, and the associated gradient.
|
||||
|
||||
See Johnson and Joannopoulos, Opt. Expr. 8, 3 (2001) for details (full
|
||||
citation in module docstring).
|
||||
|
||||
===
|
||||
|
||||
Notes on my understanding of the procedure:
|
||||
|
||||
Minimize f(Y) = |trace((Y.H @ A @ Y)|, making use of Y = Z @ inv(Z.H @ Z)^(1/2)
|
||||
(a polar orthogonalization of Y). This gives f(Z) = |trace(Z.H @ A @ Z @ U)|,
|
||||
where U = inv(Z.H @ Z). We minimize the absolute value to find the eigenvalues
|
||||
with smallest magnitude.
|
||||
|
||||
The gradient is P @ (A @ Z @ U), where P = (1 - Z @ U @ Z.H) is a projection
|
||||
onto the space orthonormal to Z. If approx_grad is True, the approximate
|
||||
inverse of the maxwell operator is used to precondition the gradient.
|
||||
"""
|
||||
z = Z.view(dtype=complex).reshape(y_shape)
|
||||
U = numpy.linalg.inv(z.conj().T @ z)
|
||||
zU = z @ U
|
||||
AzU = scipy_op @ zU
|
||||
zTAzU = z.conj().T @ AzU
|
||||
f = numpy.real(numpy.trace(zTAzU))
|
||||
if approx_grad:
|
||||
df_dy = scipy_iop @ (AzU - zU @ zTAzU)
|
||||
else:
|
||||
df_dy = (AzU - zU @ zTAzU)
|
||||
|
||||
df_dy_flat = df_dy.view(dtype=float).ravel()
|
||||
return numpy.abs(f), numpy.sign(f) * df_dy_flat
|
||||
|
||||
'''
|
||||
Use the conjugate gradient method and the approximate gradient calculation to
|
||||
quickly find approximate eigenvectors.
|
||||
'''
|
||||
result = scipy.optimize.minimize(rayleigh_quotient,
|
||||
numpy.random.rand(*y_shape, 2),
|
||||
jac=True,
|
||||
method='L-BFGS-B',
|
||||
tol=1e-20,
|
||||
options={'maxiter': 2000, 'gtol':0, 'ftol':1e-20 , 'disp':True})#, 'maxls':80, 'm':30})
|
||||
|
||||
|
||||
result = scipy.optimize.minimize(lambda y: rayleigh_quotient(y, True),
|
||||
result.x,
|
||||
jac=True,
|
||||
method='L-BFGS-B',
|
||||
tol=1e-20,
|
||||
options={'maxiter': 2000, 'gtol':0, 'disp':True})
|
||||
|
||||
result = scipy.optimize.minimize(lambda y: rayleigh_quotient(y, False),
|
||||
result.x,
|
||||
jac=True,
|
||||
method='L-BFGS-B',
|
||||
tol=1e-20,
|
||||
options={'maxiter': 2000, 'gtol':0, 'disp':True})
|
||||
|
||||
for i in range(20):
|
||||
result = scipy.optimize.minimize(lambda y: rayleigh_quotient(y, False),
|
||||
result.x,
|
||||
jac=True,
|
||||
method='L-BFGS-B',
|
||||
tol=1e-20,
|
||||
options={'maxiter': 70, 'gtol':0, 'disp':True})
|
||||
if result.nit == 0:
|
||||
# We took 0 steps, so re-running won't help
|
||||
break
|
||||
|
||||
|
||||
z = result.x.view(dtype=complex).reshape(y_shape)
|
||||
|
||||
'''
|
||||
Recover eigenvectors from Z
|
||||
'''
|
||||
U = numpy.linalg.inv(z.conj().T @ z)
|
||||
y = z @ scipy.linalg.sqrtm(U)
|
||||
w = y.conj().T @ (scipy_op @ y)
|
||||
|
||||
eigvals, w_eigvecs = numpy.linalg.eig(w)
|
||||
eigvecs = y @ w_eigvecs
|
||||
|
||||
for i in range(len(eigvals)):
|
||||
v = eigvecs[:, i]
|
||||
n = eigvals[i]
|
||||
v /= norm(v)
|
||||
eigness = norm(scipy_op @ v - (v.conj() @ (scipy_op @ v)) * v )
|
||||
f = numpy.sqrt(-numpy.real(n))
|
||||
df = numpy.sqrt(-numpy.real(n + eigness))
|
||||
neff_err = kmag * (1/df - 1/f)
|
||||
logger.info('eigness {}: {}\n neff_err: {}'.format(i, eigness, neff_err))
|
||||
|
||||
order = numpy.argsort(numpy.abs(eigvals))
|
||||
return eigvals[order], eigvecs.T[order]
|
||||
|
||||
|
||||
def find_k(frequency: float,
|
||||
tolerance: float,
|
||||
direction: numpy.ndarray,
|
||||
@ -371,7 +479,6 @@ def find_k(frequency: float,
|
||||
band: int = 0,
|
||||
k_min: float = 0,
|
||||
k_max: float = 0.5,
|
||||
solve_callback: Callable = None
|
||||
) -> Tuple[numpy.ndarray, float]:
|
||||
"""
|
||||
Search for a bloch vector that has a given frequency.
|
||||
@ -392,10 +499,8 @@ def find_k(frequency: float,
|
||||
|
||||
def get_f(k0_mag: float, band: int = 0):
|
||||
k0 = direction * k0_mag
|
||||
n, v = eigsolve(band + 1, k0, G_matrix=G_matrix, epsilon=epsilon, mu=mu)
|
||||
n, _v = eigsolve(band + 1, k0, G_matrix=G_matrix, epsilon=epsilon)
|
||||
f = numpy.sqrt(numpy.abs(numpy.real(n[band])))
|
||||
if solve_callback:
|
||||
solve_callback(k0_mag, n, v, f)
|
||||
return f
|
||||
|
||||
res = scipy.optimize.minimize_scalar(lambda x: abs(get_f(x, band) - frequency),
|
||||
@ -406,244 +511,3 @@ def find_k(frequency: float,
|
||||
return res.x * direction, res.fun + frequency
|
||||
|
||||
|
||||
def eigsolve(num_modes: int,
|
||||
k0: numpy.ndarray,
|
||||
G_matrix: numpy.ndarray,
|
||||
epsilon: field_t,
|
||||
mu: field_t = None,
|
||||
tolerance: float = 1e-20,
|
||||
max_iters: int = 10000,
|
||||
reset_iters: int = 100,
|
||||
) -> Tuple[numpy.ndarray, numpy.ndarray]:
|
||||
"""
|
||||
Find the first (lowest-frequency) num_modes eigenmodes with Bloch wavevector
|
||||
k0 of the specified structure.
|
||||
|
||||
:param k0: Bloch wavevector, [k0x, k0y, k0z].
|
||||
:param G_matrix: 3x3 matrix, with reciprocal lattice vectors as columns.
|
||||
:param epsilon: Dielectric constant distribution for the simulation.
|
||||
All fields are sampled at cell centers (i.e., NOT Yee-gridded)
|
||||
:param mu: Magnetic permability distribution for the simulation.
|
||||
Default None (1 everywhere).
|
||||
:param tolerance: Solver stops when fractional change in the objective
|
||||
trace(Z.H @ A @ Z @ inv(Z Z.H)) is smaller than the tolerance
|
||||
:return: (eigenvalues, eigenvectors) where eigenvalues[i] corresponds to the
|
||||
vector eigenvectors[i, :]
|
||||
"""
|
||||
h_size = 2 * epsilon[0].size
|
||||
|
||||
kmag = norm(G_matrix @ k0)
|
||||
|
||||
'''
|
||||
Generate the operators
|
||||
'''
|
||||
mop = maxwell_operator(k0=k0, G_matrix=G_matrix, epsilon=epsilon, mu=mu)
|
||||
imop = inverse_maxwell_operator_approx(k0=k0, G_matrix=G_matrix, epsilon=epsilon, mu=mu)
|
||||
|
||||
scipy_op = spalg.LinearOperator(dtype=complex, shape=(h_size, h_size), matvec=mop)
|
||||
scipy_iop = spalg.LinearOperator(dtype=complex, shape=(h_size, h_size), matvec=imop)
|
||||
|
||||
y_shape = (h_size, num_modes)
|
||||
|
||||
prev_E = 0
|
||||
d_scale = 1
|
||||
prev_traceGtKG = 0
|
||||
#prev_theta = 0.5
|
||||
D = numpy.zeros(shape=y_shape, dtype=complex)
|
||||
|
||||
y0 = None
|
||||
if y0 is None:
|
||||
Z = numpy.random.rand(*y_shape) + 1j * numpy.random.rand(*y_shape)
|
||||
else:
|
||||
Z = y0
|
||||
|
||||
while True:
|
||||
Z *= num_modes / norm(Z)
|
||||
ZtZ = Z.conj().T @ Z
|
||||
try:
|
||||
U = numpy.linalg.inv(ZtZ)
|
||||
except numpy.linalg.LinAlgError:
|
||||
Z = numpy.random.rand(*y_shape) + 1j * numpy.random.rand(*y_shape)
|
||||
continue
|
||||
|
||||
trace_U = real(trace(U))
|
||||
if trace_U > 1e8 * num_modes:
|
||||
Z = Z @ scipy.linalg.sqrtm(U).conj().T
|
||||
prev_traceGtKG = 0
|
||||
continue
|
||||
break
|
||||
|
||||
for i in range(max_iters):
|
||||
ZtZ = Z.conj().T @ Z
|
||||
U = numpy.linalg.inv(ZtZ)
|
||||
AZ = scipy_op @ Z
|
||||
AZU = AZ @ U
|
||||
ZtAZU = Z.conj().T @ AZU
|
||||
E_signed = real(trace(ZtAZU))
|
||||
sgn = numpy.sign(E_signed)
|
||||
E = numpy.abs(E_signed)
|
||||
G = (AZU - Z @ U @ ZtAZU) * sgn
|
||||
|
||||
if i > 0 and abs(E - prev_E) < tolerance * 0.5 * (E + prev_E + 1e-7):
|
||||
logger.info('Optimization succeded: {} - 5e-8 < {} * {} / 2'.format(abs(E - prev_E), tolerance, E + prev_E))
|
||||
break
|
||||
|
||||
KG = scipy_iop @ G
|
||||
traceGtKG = _rtrace_AtB(G, KG)
|
||||
|
||||
if prev_traceGtKG == 0 or i % reset_iters == 0:
|
||||
logger.info('CG reset')
|
||||
gamma = 0
|
||||
else:
|
||||
gamma = traceGtKG / prev_traceGtKG
|
||||
|
||||
D = gamma / d_scale * D + KG
|
||||
d_scale = num_modes / norm(D)
|
||||
D *= d_scale
|
||||
|
||||
ZtAZ = Z.conj().T @ AZ
|
||||
|
||||
AD = scipy_op @ D
|
||||
DtD = D.conj().T @ D
|
||||
DtAD = D.conj().T @ AD
|
||||
|
||||
symZtD = _symmetrize(Z.conj().T @ D)
|
||||
symZtAD = _symmetrize(Z.conj().T @ AD)
|
||||
|
||||
Qi_memo = [None, None]
|
||||
def Qi_func(theta):
|
||||
nonlocal Qi_memo
|
||||
if Qi_memo[0] == theta:
|
||||
return Qi_memo[1]
|
||||
|
||||
c = numpy.cos(theta)
|
||||
s = numpy.sin(theta)
|
||||
Q = c*c * ZtZ + s*s * DtD + 2*s*c * symZtD
|
||||
try:
|
||||
Qi = numpy.linalg.inv(Q)
|
||||
except numpy.linalg.LinAlgError:
|
||||
logger.info('taylor Qi')
|
||||
# if c or s small, taylor expand
|
||||
if c < 1e-4 * s and c != 0:
|
||||
DtDi = numpy.linalg.inv(DtD)
|
||||
Qi = DtDi / (s*s) - 2*c/(s*s*s) * (DtDi @ (DtDi @ symZtD).conj().T)
|
||||
elif s < 1e-4 * c and s != 0:
|
||||
ZtZi = numpy.linalg.inv(ZtZ)
|
||||
Qi = ZtZi / (c*c) - 2*s/(c*c*c) * (ZtZi @ (ZtZi @ symZtD).conj().T)
|
||||
else:
|
||||
raise Exception('Inexplicable singularity in trace_func')
|
||||
Qi_memo[0] = theta
|
||||
Qi_memo[1] = Qi
|
||||
return Qi
|
||||
|
||||
def trace_func(theta):
|
||||
c = numpy.cos(theta)
|
||||
s = numpy.sin(theta)
|
||||
Qi = Qi_func(theta)
|
||||
R = c*c * ZtAZ + s*s * DtAD + 2*s*c * symZtAD
|
||||
trace = _rtrace_AtB(R, Qi)
|
||||
return numpy.abs(trace)
|
||||
|
||||
'''
|
||||
def trace_deriv(theta):
|
||||
Qi = Qi_func(theta)
|
||||
c2 = numpy.cos(2 * theta)
|
||||
s2 = numpy.sin(2 * theta)
|
||||
F = -0.5*s2 * (ZtAZ - DtAD) + c2 * symZtAD
|
||||
trace_deriv = _rtrace_AtB(Qi, F)
|
||||
|
||||
G = Qi @ F.conj().T @ Qi.conj().T
|
||||
H = -0.5*s2 * (ZtZ - DtD) + c2 * symZtD
|
||||
trace_deriv -= _rtrace_AtB(G, H)
|
||||
|
||||
trace_deriv *= 2
|
||||
return trace_deriv * sgn
|
||||
|
||||
U_sZtD = U @ symZtD
|
||||
|
||||
dE = 2.0 * (_rtrace_AtB(U, symZtAD) -
|
||||
_rtrace_AtB(ZtAZU, U_sZtD))
|
||||
|
||||
d2E = 2 * (_rtrace_AtB(U, DtAD) -
|
||||
_rtrace_AtB(ZtAZU, U @ (DtD - 4 * symZtD @ U_sZtD)) -
|
||||
4 * _rtrace_AtB(U, symZtAD @ U_sZtD))
|
||||
|
||||
# Newton-Raphson to find a root of the first derivative:
|
||||
theta = -dE/d2E
|
||||
|
||||
if d2E < 0 or abs(theta) >= pi:
|
||||
theta = -abs(prev_theta) * numpy.sign(dE)
|
||||
|
||||
# theta, new_E, new_dE = linmin(theta, E, dE, 0.1, min(tolerance, 1e-6), 1e-14, 0, -numpy.sign(dE) * K_PI, trace_func)
|
||||
theta, n, _, new_E, _, _new_dE = scipy.optimize.line_search(trace_func, trace_deriv, xk=theta, pk=numpy.ones((1,1)), gfk=dE, old_fval=E, c1=min(tolerance, 1e-6), c2=0.1, amax=pi)
|
||||
'''
|
||||
result = scipy.optimize.minimize_scalar(trace_func, bounds=(0, pi), tol=tolerance)
|
||||
new_E = result.fun
|
||||
theta = result.x
|
||||
|
||||
improvement = numpy.abs(E - new_E) * 2 / numpy.abs(E + new_E)
|
||||
logger.info('linmin improvement {}'.format(improvement))
|
||||
Z *= numpy.cos(theta)
|
||||
Z += D * numpy.sin(theta)
|
||||
|
||||
prev_traceGtKG = traceGtKG
|
||||
#prev_theta = theta
|
||||
prev_E = E
|
||||
|
||||
'''
|
||||
Recover eigenvectors from Z
|
||||
'''
|
||||
U = numpy.linalg.inv(Z.conj().T @ Z)
|
||||
Y = Z @ scipy.linalg.sqrtm(U)
|
||||
W = Y.conj().T @ (scipy_op @ Y)
|
||||
|
||||
eigvals, W_eigvecs = numpy.linalg.eig(W)
|
||||
eigvecs = Y @ W_eigvecs
|
||||
|
||||
for i in range(len(eigvals)):
|
||||
v = eigvecs[:, i]
|
||||
n = eigvals[i]
|
||||
v /= norm(v)
|
||||
eigness = norm(scipy_op @ v - (v.conj() @ (scipy_op @ v)) * v )
|
||||
f = numpy.sqrt(-numpy.real(n))
|
||||
df = numpy.sqrt(-numpy.real(n + eigness))
|
||||
neff_err = kmag * (1/df - 1/f)
|
||||
logger.info('eigness {}: {}\n neff_err: {}'.format(i, eigness, neff_err))
|
||||
|
||||
order = numpy.argsort(numpy.abs(eigvals))
|
||||
return eigvals[order], eigvecs.T[order]
|
||||
|
||||
'''
|
||||
def linmin(x_guess, f0, df0, x_max, f_tol=0.1, df_tol=min(tolerance, 1e-6), x_tol=1e-14, x_min=0, linmin_func):
|
||||
if df0 > 0:
|
||||
x0, f0, df0 = linmin(-x_guess, f0, -df0, -x_max, f_tol, df_tol, x_tol, -x_min, lambda q, dq: -linmin_func(q, dq))
|
||||
return -x0, f0, -df0
|
||||
elif df0 == 0:
|
||||
return 0, f0, df0
|
||||
else:
|
||||
x = x_guess
|
||||
fx = f0
|
||||
dfx = df0
|
||||
|
||||
isave = numpy.zeros((2,), numpy.intc)
|
||||
dsave = numpy.zeros((13,), float)
|
||||
|
||||
x, fx, dfx, task = minpack2.dsrch(x, fx, dfx, f_tol, df_tol, x_tol, task,
|
||||
x_min, x_max, isave, dsave)
|
||||
for i in range(int(1e6)):
|
||||
if task != 'F':
|
||||
logging.info('search converged in {} iterations'.format(i))
|
||||
break
|
||||
fx = f(x, dfx)
|
||||
x, fx, dfx, task = minpack2.dsrch(x, fx, dfx, f_tol, df_tol, x_tol, task,
|
||||
x_min, x_max, isave, dsave)
|
||||
|
||||
return x, fx, dfx
|
||||
'''
|
||||
|
||||
def _rtrace_AtB(A, B):
|
||||
return real(numpy.sum(A.conj() * B))
|
||||
|
||||
def _symmetrize(A):
|
||||
return (A + A.conj().T) * 0.5
|
||||
|
@ -6,11 +6,9 @@ import numpy
|
||||
from numpy.fft import fft2, fftshift, fftfreq, ifft2, ifftshift
|
||||
from numpy import pi
|
||||
|
||||
from .. import field_t
|
||||
|
||||
|
||||
def near_to_farfield(E_near: field_t,
|
||||
H_near: field_t,
|
||||
def near_to_farfield(E_near: List[numpy.ndarray],
|
||||
H_near: List[numpy.ndarray],
|
||||
dx: float,
|
||||
dy: float,
|
||||
padded_size: List[int] = None
|
||||
@ -117,8 +115,8 @@ def near_to_farfield(E_near: field_t,
|
||||
|
||||
|
||||
|
||||
def far_to_nearfield(E_far: field_t,
|
||||
H_far: field_t,
|
||||
def far_to_nearfield(E_far: List[numpy.ndarray],
|
||||
H_far: List[numpy.ndarray],
|
||||
dkx: float,
|
||||
dky: float,
|
||||
padded_size: List[int] = None
|
239
fdfd_tools/fdtd.py
Normal file
239
fdfd_tools/fdtd.py
Normal file
@ -0,0 +1,239 @@
|
||||
from typing import List, Callable, Tuple, Dict
|
||||
import numpy
|
||||
|
||||
from . import dx_lists_t, field_t
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
|
||||
|
||||
functional_matrix = Callable[[field_t], field_t]
|
||||
|
||||
|
||||
def curl_h(dxes: dx_lists_t = None) -> functional_matrix:
|
||||
"""
|
||||
Curl operator for use with the H field.
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Function for taking the discretized curl of the H-field, F(H) -> curlH
|
||||
"""
|
||||
if dxes:
|
||||
dxyz_b = numpy.meshgrid(*dxes[1], indexing='ij')
|
||||
|
||||
def dh(f, ax):
|
||||
return (f - numpy.roll(f, 1, axis=ax)) / dxyz_b[ax]
|
||||
else:
|
||||
def dh(f, ax):
|
||||
return f - numpy.roll(f, 1, axis=ax)
|
||||
|
||||
def ch_fun(h: field_t) -> field_t:
|
||||
e = [dh(h[2], 1) - dh(h[1], 2),
|
||||
dh(h[0], 2) - dh(h[2], 0),
|
||||
dh(h[1], 0) - dh(h[0], 1)]
|
||||
return e
|
||||
|
||||
return ch_fun
|
||||
|
||||
|
||||
def curl_e(dxes: dx_lists_t = None) -> functional_matrix:
|
||||
"""
|
||||
Curl operator for use with the E field.
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Function for taking the discretized curl of the E-field, F(E) -> curlE
|
||||
"""
|
||||
if dxes is not None:
|
||||
dxyz_a = numpy.meshgrid(*dxes[0], indexing='ij')
|
||||
|
||||
def de(f, ax):
|
||||
return (numpy.roll(f, -1, axis=ax) - f) / dxyz_a[ax]
|
||||
else:
|
||||
def de(f, ax):
|
||||
return numpy.roll(f, -1, axis=ax) - f
|
||||
|
||||
def ce_fun(e: field_t) -> field_t:
|
||||
h = [de(e[2], 1) - de(e[1], 2),
|
||||
de(e[0], 2) - de(e[2], 0),
|
||||
de(e[1], 0) - de(e[0], 1)]
|
||||
return h
|
||||
|
||||
return ce_fun
|
||||
|
||||
|
||||
def maxwell_e(dt: float, dxes: dx_lists_t = None) -> functional_matrix:
|
||||
curl_h_fun = curl_h(dxes)
|
||||
|
||||
def me_fun(e: field_t, h: field_t, epsilon: field_t):
|
||||
ch = curl_h_fun(h)
|
||||
for ei, ci, epsi in zip(e, ch, epsilon):
|
||||
ei += dt * ci / epsi
|
||||
return e
|
||||
|
||||
return me_fun
|
||||
|
||||
|
||||
def maxwell_h(dt: float, dxes: dx_lists_t = None) -> functional_matrix:
|
||||
curl_e_fun = curl_e(dxes)
|
||||
|
||||
def mh_fun(e: field_t, h: field_t):
|
||||
ce = curl_e_fun(e)
|
||||
for hi, ci in zip(h, ce):
|
||||
hi -= dt * ci
|
||||
return h
|
||||
|
||||
return mh_fun
|
||||
|
||||
|
||||
def conducting_boundary(direction: int,
|
||||
polarity: int
|
||||
) -> Tuple[functional_matrix, functional_matrix]:
|
||||
dirs = [0, 1, 2]
|
||||
if direction not in dirs:
|
||||
raise Exception('Invalid direction: {}'.format(direction))
|
||||
dirs.remove(direction)
|
||||
u, v = dirs
|
||||
|
||||
if polarity < 0:
|
||||
boundary_slice = [slice(None)] * 3
|
||||
shifted1_slice = [slice(None)] * 3
|
||||
boundary_slice[direction] = 0
|
||||
shifted1_slice[direction] = 1
|
||||
|
||||
def en(e: field_t):
|
||||
e[direction][boundary_slice] = 0
|
||||
e[u][boundary_slice] = e[u][shifted1_slice]
|
||||
e[v][boundary_slice] = e[v][shifted1_slice]
|
||||
return e
|
||||
|
||||
def hn(h: field_t):
|
||||
h[direction][boundary_slice] = h[direction][shifted1_slice]
|
||||
h[u][boundary_slice] = 0
|
||||
h[v][boundary_slice] = 0
|
||||
return h
|
||||
|
||||
return en, hn
|
||||
|
||||
elif polarity > 0:
|
||||
boundary_slice = [slice(None)] * 3
|
||||
shifted1_slice = [slice(None)] * 3
|
||||
shifted2_slice = [slice(None)] * 3
|
||||
boundary_slice[direction] = -1
|
||||
shifted1_slice[direction] = -2
|
||||
shifted2_slice[direction] = -3
|
||||
|
||||
def ep(e: field_t):
|
||||
e[direction][boundary_slice] = -e[direction][shifted2_slice]
|
||||
e[direction][shifted1_slice] = 0
|
||||
e[u][boundary_slice] = e[u][shifted1_slice]
|
||||
e[v][boundary_slice] = e[v][shifted1_slice]
|
||||
return e
|
||||
|
||||
def hp(h: field_t):
|
||||
h[direction][boundary_slice] = h[direction][shifted1_slice]
|
||||
h[u][boundary_slice] = -h[u][shifted2_slice]
|
||||
h[u][shifted1_slice] = 0
|
||||
h[v][boundary_slice] = -h[v][shifted2_slice]
|
||||
h[v][shifted1_slice] = 0
|
||||
return h
|
||||
|
||||
return ep, hp
|
||||
|
||||
else:
|
||||
raise Exception('Bad polarity: {}'.format(polarity))
|
||||
|
||||
|
||||
def cpml(direction:int,
|
||||
polarity: int,
|
||||
dt: float,
|
||||
epsilon: field_t,
|
||||
thickness: int = 8,
|
||||
epsilon_eff: float = 1,
|
||||
dtype: numpy.dtype = numpy.float32,
|
||||
) -> Tuple[Callable, Callable, Dict[str, field_t]]:
|
||||
|
||||
if direction not in range(3):
|
||||
raise Exception('Invalid direction: {}'.format(direction))
|
||||
|
||||
if polarity not in (-1, 1):
|
||||
raise Exception('Invalid polarity: {}'.format(polarity))
|
||||
|
||||
if thickness <= 2:
|
||||
raise Exception('It would be wise to have a pml with 4+ cells of thickness')
|
||||
|
||||
if epsilon_eff <= 0:
|
||||
raise Exception('epsilon_eff must be positive')
|
||||
|
||||
m = (3.5, 1)
|
||||
sigma_max = 0.8 * (m[0] + 1) / numpy.sqrt(epsilon_eff)
|
||||
alpha_max = 0 # TODO: Decide what to do about non-zero alpha
|
||||
transverse = numpy.delete(range(3), direction)
|
||||
u, v = transverse
|
||||
|
||||
xe = numpy.arange(1, thickness+1, dtype=float)
|
||||
xh = numpy.arange(1, thickness+1, dtype=float)
|
||||
if polarity > 0:
|
||||
xe -= 0.5
|
||||
elif polarity < 0:
|
||||
xh -= 0.5
|
||||
xe = xe[::-1]
|
||||
xh = xh[::-1]
|
||||
else:
|
||||
raise Exception('Bad polarity!')
|
||||
|
||||
expand_slice = [None] * 3
|
||||
expand_slice[direction] = slice(None)
|
||||
|
||||
def par(x):
|
||||
sigma = ((x / thickness) ** m[0]) * sigma_max
|
||||
alpha = ((1 - x / thickness) ** m[1]) * alpha_max
|
||||
p0 = numpy.exp(-(sigma + alpha) * dt)
|
||||
p1 = sigma / (sigma + alpha) * (p0 - 1)
|
||||
return p0[expand_slice], p1[expand_slice]
|
||||
|
||||
p0e, p1e = par(xe)
|
||||
p0h, p1h = par(xh)
|
||||
|
||||
region = [slice(None)] * 3
|
||||
if polarity < 0:
|
||||
region[direction] = slice(None, thickness)
|
||||
elif polarity > 0:
|
||||
region[direction] = slice(-thickness, None)
|
||||
else:
|
||||
raise Exception('Bad polarity!')
|
||||
|
||||
if direction == 1:
|
||||
se = 1
|
||||
else:
|
||||
se = -1
|
||||
|
||||
# TODO check if epsilon is uniform?
|
||||
shape = list(epsilon[0].shape)
|
||||
shape[direction] = thickness
|
||||
psi_e = [numpy.zeros(shape, dtype=dtype), numpy.zeros(shape, dtype=dtype)]
|
||||
psi_h = [numpy.zeros(shape, dtype=dtype), numpy.zeros(shape, dtype=dtype)]
|
||||
|
||||
fields = {
|
||||
'psi_e_u': psi_e[0],
|
||||
'psi_e_v': psi_e[1],
|
||||
'psi_h_u': psi_h[0],
|
||||
'psi_h_v': psi_h[1],
|
||||
}
|
||||
|
||||
def pml_e(e: field_t, h: field_t, epsilon: field_t) -> Tuple[field_t, field_t]:
|
||||
psi_e[0] *= p0e
|
||||
psi_e[0] += p1e * (h[v][region] - numpy.roll(h[v], 1, axis=direction)[region])
|
||||
psi_e[1] *= p0e
|
||||
psi_e[1] += p1e * (h[u][region] - numpy.roll(h[u], 1, axis=direction)[region])
|
||||
e[u][region] += se * dt * psi_e[0] / epsilon[u][region]
|
||||
e[v][region] -= se * dt * psi_e[1] / epsilon[v][region]
|
||||
return e, h
|
||||
|
||||
def pml_h(e: field_t, h: field_t) -> Tuple[field_t, field_t]:
|
||||
psi_h[0] *= p0h
|
||||
psi_h[0] += p1h * (numpy.roll(e[v], -1, axis=direction)[region] - e[v][region])
|
||||
psi_h[1] *= p0h
|
||||
psi_h[1] += p1h * (numpy.roll(e[u], -1, axis=direction)[region] - e[u][region])
|
||||
h[u][region] -= se * dt * psi_h[0]
|
||||
h[v][region] += se * dt * psi_h[1]
|
||||
return e, h
|
||||
|
||||
return pml_e, pml_h, fields
|
@ -2,13 +2,13 @@
|
||||
Functional versions of many FDFD operators. These can be useful for performing
|
||||
FDFD calculations without needing to construct large matrices in memory.
|
||||
|
||||
The functions generated here expect field inputs with shape (3, X, Y, Z),
|
||||
e.g. E = [E_x, E_y, E_z] where each component has shape (X, Y, Z)
|
||||
The functions generated here expect inputs in the form E = [E_x, E_y, E_z], where each
|
||||
component E_* is an ndarray of equal shape.
|
||||
"""
|
||||
from typing import List, Callable
|
||||
import numpy
|
||||
|
||||
from .. import dx_lists_t, field_t
|
||||
from . import dx_lists_t, field_t
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
|
||||
@ -20,7 +20,7 @@ def curl_h(dxes: dx_lists_t) -> functional_matrix:
|
||||
"""
|
||||
Curl operator for use with the H field.
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Function for taking the discretized curl of the H-field, F(H) -> curlH
|
||||
"""
|
||||
dxyz_b = numpy.meshgrid(*dxes[1], indexing='ij')
|
||||
@ -29,13 +29,9 @@ def curl_h(dxes: dx_lists_t) -> functional_matrix:
|
||||
return (f - numpy.roll(f, 1, axis=ax)) / dxyz_b[ax]
|
||||
|
||||
def ch_fun(h: field_t) -> field_t:
|
||||
e = numpy.empty_like(h)
|
||||
e[0] = dh(h[2], 1)
|
||||
e[0] -= dh(h[1], 2)
|
||||
e[1] = dh(h[0], 2)
|
||||
e[1] -= dh(h[2], 0)
|
||||
e[2] = dh(h[1], 0)
|
||||
e[2] -= dh(h[0], 1)
|
||||
e = [dh(h[2], 1) - dh(h[1], 2),
|
||||
dh(h[0], 2) - dh(h[2], 0),
|
||||
dh(h[1], 0) - dh(h[0], 1)]
|
||||
return e
|
||||
|
||||
return ch_fun
|
||||
@ -45,7 +41,7 @@ def curl_e(dxes: dx_lists_t) -> functional_matrix:
|
||||
"""
|
||||
Curl operator for use with the E field.
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Function for taking the discretized curl of the E-field, F(E) -> curlE
|
||||
"""
|
||||
dxyz_a = numpy.meshgrid(*dxes[0], indexing='ij')
|
||||
@ -54,13 +50,9 @@ def curl_e(dxes: dx_lists_t) -> functional_matrix:
|
||||
return (numpy.roll(f, -1, axis=ax) - f) / dxyz_a[ax]
|
||||
|
||||
def ce_fun(e: field_t) -> field_t:
|
||||
h = numpy.empty_like(e)
|
||||
h[0] = de(e[2], 1)
|
||||
h[0] -= de(e[1], 2)
|
||||
h[1] = de(e[0], 2)
|
||||
h[1] -= de(e[2], 0)
|
||||
h[2] = de(e[1], 0)
|
||||
h[2] -= de(e[0], 1)
|
||||
h = [de(e[2], 1) - de(e[1], 2),
|
||||
de(e[0], 2) - de(e[2], 0),
|
||||
de(e[1], 0) - de(e[0], 1)]
|
||||
return h
|
||||
|
||||
return ce_fun
|
||||
@ -77,7 +69,7 @@ def e_full(omega: complex,
|
||||
(del x (1/mu * del x) - omega**2 * epsilon) E = -i * omega * J
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param epsilon: Dielectric constant
|
||||
:param mu: Magnetic permeability (default 1 everywhere)
|
||||
:return: Function implementing the wave operator A(E) -> E
|
||||
@ -87,11 +79,11 @@ def e_full(omega: complex,
|
||||
|
||||
def op_1(e):
|
||||
curls = ch(ce(e))
|
||||
return curls - omega ** 2 * epsilon * e
|
||||
return [c - omega ** 2 * e * x for c, e, x in zip(curls, epsilon, e)]
|
||||
|
||||
def op_mu(e):
|
||||
curls = ch(mu * ce(e))
|
||||
return curls - omega ** 2 * epsilon * e
|
||||
curls = ch([m * y for m, y in zip(mu, ce(e))])
|
||||
return [c - omega ** 2 * p * x for c, p, x in zip(curls, epsilon, e)]
|
||||
|
||||
if numpy.any(numpy.equal(mu, None)):
|
||||
return op_1
|
||||
@ -108,7 +100,7 @@ def eh_full(omega: complex,
|
||||
Wave operator for full (both E and H) field representation.
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param epsilon: Dielectric constant
|
||||
:param mu: Magnetic permeability (default 1 everywhere)
|
||||
:return: Function implementing the wave operator A(E, H) -> (E, H)
|
||||
@ -117,12 +109,12 @@ def eh_full(omega: complex,
|
||||
ce = curl_e(dxes)
|
||||
|
||||
def op_1(e, h):
|
||||
return (ch(h) - 1j * omega * epsilon * e,
|
||||
ce(e) + 1j * omega * h)
|
||||
return ([c - 1j * omega * p * x for c, p, x in zip(ch(h), epsilon, e)],
|
||||
[c + 1j * omega * y for c, y in zip(ce(e), h)])
|
||||
|
||||
def op_mu(e, h):
|
||||
return (ch(h) - 1j * omega * epsilon * e,
|
||||
ce(e) + 1j * omega * mu * h)
|
||||
return ([c - 1j * omega * p * x for c, p, x in zip(ch(h), epsilon, e)],
|
||||
[c + 1j * omega * m * y for c, m, y in zip(ce(e), mu, h)])
|
||||
|
||||
if numpy.any(numpy.equal(mu, None)):
|
||||
return op_1
|
||||
@ -139,68 +131,19 @@ def e2h(omega: complex,
|
||||
For use with e_full -- assumes that there is no magnetic current M.
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param mu: Magnetic permeability (default 1 everywhere)
|
||||
:return: Function for converting E to H
|
||||
"""
|
||||
A2 = curl_e(dxes)
|
||||
|
||||
def e2h_1_1(e):
|
||||
return A2(e) / (-1j * omega)
|
||||
return [y / (-1j * omega) for y in A2(e)]
|
||||
|
||||
def e2h_mu(e):
|
||||
return A2(e) / (-1j * omega * mu)
|
||||
return [y / (-1j * omega * m) for y, m in zip(A2(e), mu)]
|
||||
|
||||
if numpy.any(numpy.equal(mu, None)):
|
||||
return e2h_1_1
|
||||
else:
|
||||
return e2h_mu
|
||||
|
||||
|
||||
def m2j(omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
mu: field_t = None,
|
||||
) -> functional_matrix:
|
||||
"""
|
||||
Utility operator for converting magnetic current (M) distribution
|
||||
into equivalent electric current distribution (J).
|
||||
For use with e.g. e_full().
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param mu: Magnetic permeability (default 1 everywhere)
|
||||
:return: Function for converting M to J
|
||||
"""
|
||||
ch = curl_h(dxes)
|
||||
|
||||
def m2j_mu(m):
|
||||
J = ch(m / mu) / (-1j * omega)
|
||||
return J
|
||||
|
||||
def m2j_1(m):
|
||||
J = ch(m) / (-1j * omega)
|
||||
return J
|
||||
|
||||
if numpy.any(numpy.equal(mu, None)):
|
||||
return m2j_1
|
||||
else:
|
||||
return m2j_mu
|
||||
|
||||
|
||||
def e_tfsf_source(TF_region: field_t,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: field_t,
|
||||
mu: field_t = None,
|
||||
) -> functional_matrix:
|
||||
"""
|
||||
Operator that turuns an E-field distribution into a total-field/scattered-field
|
||||
(TFSF) source.
|
||||
"""
|
||||
# TODO documentation
|
||||
A = e_full(omega, dxes, epsilon, mu)
|
||||
|
||||
def op(e):
|
||||
neg_iwj = A(TF_region * e) - TF_region * A(e)
|
||||
return neg_iwj / (-1j * omega)
|
||||
|
@ -5,11 +5,10 @@ Functions for creating stretched coordinate PMLs.
|
||||
from typing import List, Callable
|
||||
import numpy
|
||||
|
||||
from .. import dx_lists_t
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
|
||||
|
||||
dx_lists_t = List[List[numpy.ndarray]]
|
||||
s_function_type = Callable[[float], float]
|
||||
|
||||
|
@ -3,13 +3,17 @@ Sparse matrix operators for use with electromagnetic wave equations.
|
||||
|
||||
These functions return sparse-matrix (scipy.sparse.spmatrix) representations of
|
||||
a variety of operators, intended for use with E and H fields vectorized using the
|
||||
meanas.vec() and .unvec() functions (column-major/Fortran ordering).
|
||||
fdfd_tools.vec() and .unvec() functions (column-major/Fortran ordering).
|
||||
|
||||
E- and H-field values are defined on a Yee cell; epsilon values should be calculated for
|
||||
cells centered at each E component (mu at each H component).
|
||||
|
||||
Many of these functions require a 'dxes' parameter, of type meanas.dx_lists_type; see
|
||||
the meanas.types submodule for details.
|
||||
Many of these functions require a 'dxes' parameter, of type fdfd_tools.dx_lists_type,
|
||||
which contains grid cell width information in the following format:
|
||||
[[[dx_e_0, dx_e_1, ...], [dy_e_0, ...], [dz_e_0, ...]],
|
||||
[[dx_h_0, dx_h_1, ...], [dy_h_0, ...], [dz_h_0, ...]]]
|
||||
where dx_e_0 is the x-width of the x=0 cells, as used when calculating dE/dx,
|
||||
and dy_h_0 is the y-width of the y=0 cells, as used when calculating dH/dy, etc.
|
||||
|
||||
|
||||
The following operators are included:
|
||||
@ -32,7 +36,7 @@ from typing import List, Tuple
|
||||
import numpy
|
||||
import scipy.sparse as sparse
|
||||
|
||||
from .. import vec, dx_lists_t, vfield_t
|
||||
from . import vec, dx_lists_t, vfield_t
|
||||
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
@ -53,7 +57,7 @@ def e_full(omega: complex,
|
||||
To make this matrix symmetric, use the preconditions from e_full_preconditioners().
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param epsilon: Vectorized dielectric constant
|
||||
:param mu: Vectorized magnetic permeability (default 1 everywhere).
|
||||
:param pec: Vectorized mask specifying PEC cells. Any cells where pec != 0 are interpreted
|
||||
@ -97,7 +101,7 @@ def e_full_preconditioners(dxes: dx_lists_t
|
||||
|
||||
The preconditioner matrices are diagonal and complex, with Pr = 1 / Pl
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Preconditioner matrices (Pl, Pr)
|
||||
"""
|
||||
p_squared = [dxes[0][0][:, None, None] * dxes[1][1][None, :, None] * dxes[1][2][None, None, :],
|
||||
@ -123,7 +127,7 @@ def h_full(omega: complex,
|
||||
(del x (1/epsilon * del x) - omega**2 * mu) H = i * omega * M
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param epsilon: Vectorized dielectric constant
|
||||
:param mu: Vectorized magnetic permeability (default 1 everywhere)
|
||||
:param pec: Vectorized mask specifying PEC cells. Any cells where pec != 0 are interpreted
|
||||
@ -173,7 +177,7 @@ def eh_full(omega: complex,
|
||||
for use with a field vector of the form hstack(vec(E), vec(H)).
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param epsilon: Vectorized dielectric constant
|
||||
:param mu: Vectorized magnetic permeability (default 1 everywhere)
|
||||
:param pec: Vectorized mask specifying PEC cells. Any cells where pec != 0 are interpreted
|
||||
@ -212,7 +216,7 @@ def curl_h(dxes: dx_lists_t) -> sparse.spmatrix:
|
||||
"""
|
||||
Curl operator for use with the H field.
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Sparse matrix for taking the discretized curl of the H-field
|
||||
"""
|
||||
return cross(deriv_back(dxes[1]))
|
||||
@ -222,7 +226,7 @@ def curl_e(dxes: dx_lists_t) -> sparse.spmatrix:
|
||||
"""
|
||||
Curl operator for use with the E field.
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Sparse matrix for taking the discretized curl of the E-field
|
||||
"""
|
||||
return cross(deriv_forward(dxes[0]))
|
||||
@ -238,7 +242,7 @@ def e2h(omega: complex,
|
||||
For use with e_full -- assumes that there is no magnetic current M.
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param mu: Vectorized magnetic permeability (default 1 everywhere)
|
||||
:param pmc: Vectorized mask specifying PMC cells. Any cells where pmc != 0 are interpreted
|
||||
as containing a perfect magnetic conductor (PMC).
|
||||
@ -266,7 +270,7 @@ def m2j(omega: complex,
|
||||
For use with eg. e_full.
|
||||
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param mu: Vectorized magnetic permeability (default 1 everywhere)
|
||||
:return: Sparse matrix for converting E to H
|
||||
"""
|
||||
@ -341,7 +345,9 @@ def shift_with_mirror(axis: int, shape: List[int], shift_distance: int=1) -> spa
|
||||
|
||||
n = numpy.prod(shape)
|
||||
i_ind = numpy.arange(n)
|
||||
j_ind = numpy.ravel_multi_index(ijk, shape, order='C')
|
||||
j_ind = ijk[0] + ijk[1] * shape[0]
|
||||
if len(shape) == 3:
|
||||
j_ind += ijk[2] * shape[0] * shape[1]
|
||||
|
||||
vij = (numpy.ones(n), (i_ind, j_ind.ravel(order='C')))
|
||||
|
||||
@ -445,10 +451,10 @@ def avgb(axis: int, shape: List[int]) -> sparse.spmatrix:
|
||||
|
||||
def poynting_e_cross(e: vfield_t, dxes: dx_lists_t) -> sparse.spmatrix:
|
||||
"""
|
||||
Operator for computing the Poynting vector, containing the (E x) portion of the Poynting vector.
|
||||
Operator for computing the Poynting vector, contining the (E x) portion of the Poynting vector.
|
||||
|
||||
:param e: Vectorized E-field for the ExH cross product
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Sparse matrix containing (E x) portion of Poynting cross product
|
||||
"""
|
||||
shape = [len(dx) for dx in dxes[0]]
|
||||
@ -477,7 +483,7 @@ def poynting_h_cross(h: vfield_t, dxes: dx_lists_t) -> sparse.spmatrix:
|
||||
Operator for computing the Poynting vector, containing the (H x) portion of the Poynting vector.
|
||||
|
||||
:param h: Vectorized H-field for the HxE cross product
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:return: Sparse matrix containing (H x) portion of Poynting cross product
|
||||
"""
|
||||
shape = [len(dx) for dx in dxes[0]]
|
||||
@ -499,50 +505,3 @@ def poynting_h_cross(h: vfield_t, dxes: dx_lists_t) -> sparse.spmatrix:
|
||||
[ bx @ Hz @ fy @ dagx, zero, -bz @ Hx @ fy @ dagz],
|
||||
[-bx @ Hy @ fz @ dagx, by @ Hx @ fz @ dagy, zero]])
|
||||
return P
|
||||
|
||||
|
||||
def e_tfsf_source(TF_region: vfield_t,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None,
|
||||
) -> sparse.spmatrix:
|
||||
"""
|
||||
Operator that turns an E-field distribution into a total-field/scattered-field
|
||||
(TFSF) source.
|
||||
"""
|
||||
# TODO documentation
|
||||
A = e_full(omega, dxes, epsilon, mu)
|
||||
Q = sparse.diags(TF_region)
|
||||
return (A @ Q - Q @ A) / (-1j * omega)
|
||||
|
||||
|
||||
def e_boundary_source(mask: vfield_t,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None,
|
||||
periodic_mask_edges: bool = False,
|
||||
) -> sparse.spmatrix:
|
||||
"""
|
||||
Operator that turns an E-field distrubtion into a current (J) distribution
|
||||
along the edges (external and internal) of the provided mask. This is just an
|
||||
e_tfsf_source with an additional masking step.
|
||||
"""
|
||||
full = e_tfsf_source(TF_region=mask, omega=omega, dxes=dxes, epsilon=epsilon, mu=mu)
|
||||
|
||||
shape = [len(dxe) for dxe in dxes[0]]
|
||||
jmask = numpy.zeros_like(mask, dtype=bool)
|
||||
|
||||
if periodic_mask_edges:
|
||||
shift = lambda axis, polarity: rotation(axis=axis, shape=shape, shift_distance=polarity)
|
||||
else:
|
||||
shift = lambda axis, polarity: shift_with_mirror(axis=axis, shape=shape, shift_distance=polarity)
|
||||
|
||||
for axis in (0, 1, 2):
|
||||
for polarity in (-1, +1):
|
||||
r = shift(axis, polarity) - sparse.eye(numpy.prod(shape)) # shifted minus original
|
||||
r3 = sparse.block_diag((r, r, r))
|
||||
jmask = numpy.logical_or(jmask, numpy.abs(r3 @ mask))
|
||||
|
||||
return sparse.diags(jmask.astype(int)) @ full
|
@ -70,7 +70,7 @@ def generic(omega: complex,
|
||||
"""
|
||||
Conjugate gradient FDFD solver using CSR sparse matrices.
|
||||
|
||||
All ndarray arguments should be 1D array, as returned by meanas.vec().
|
||||
All ndarray arguments should be 1D array, as returned by fdfd_tools.vec().
|
||||
|
||||
:param omega: Complex frequency to solve at.
|
||||
:param dxes: [[dx_e, dy_e, dz_e], [dx_h, dy_h, dz_h]] (complex cell sizes)
|
@ -4,14 +4,16 @@ and a 1D array representation of that field [f_x0, f_x1, f_x2,... f_y0,... f_z0,
|
||||
Vectorized versions of the field use row-major (ie., C-style) ordering.
|
||||
"""
|
||||
|
||||
|
||||
from typing import List
|
||||
import numpy
|
||||
|
||||
from .types import field_t, vfield_t
|
||||
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
|
||||
# Types
|
||||
field_t = List[numpy.ndarray] # vector field (eg. [E_x, E_y, E_z]
|
||||
vfield_t = numpy.ndarray # linearized vector field
|
||||
|
||||
|
||||
def vec(f: field_t) -> vfield_t:
|
||||
"""
|
||||
@ -25,7 +27,7 @@ def vec(f: field_t) -> vfield_t:
|
||||
"""
|
||||
if numpy.any(numpy.equal(f, None)):
|
||||
return None
|
||||
return numpy.ravel(f, order='C')
|
||||
return numpy.hstack(tuple((fi.ravel(order='C') for fi in f)))
|
||||
|
||||
|
||||
def unvec(v: vfield_t, shape: numpy.ndarray) -> field_t:
|
||||
@ -43,5 +45,5 @@ def unvec(v: vfield_t, shape: numpy.ndarray) -> field_t:
|
||||
"""
|
||||
if numpy.any(numpy.equal(v, None)):
|
||||
return None
|
||||
return v.reshape((3, *shape), order='C')
|
||||
return [vi.reshape(shape, order='C') for vi in numpy.split(v, 3)]
|
||||
|
@ -17,50 +17,24 @@ As the z-dependence is known, all the functions in this file assume a 2D grid
|
||||
(ie. dxes = [[[dx_e_0, dx_e_1, ...], [dy_e_0, ...]], [[dx_h_0, ...], [dy_h_0, ...]]])
|
||||
with propagation along the z axis.
|
||||
"""
|
||||
# TODO update module docs
|
||||
|
||||
from typing import List, Tuple
|
||||
import numpy
|
||||
from numpy.linalg import norm
|
||||
import scipy.sparse as sparse
|
||||
|
||||
from .. import vec, unvec, dx_lists_t, field_t, vfield_t
|
||||
from . import vec, unvec, dx_lists_t, field_t, vfield_t
|
||||
from . import operators
|
||||
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
|
||||
|
||||
def operator_e(omega: complex,
|
||||
def operator(omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None,
|
||||
) -> sparse.spmatrix:
|
||||
if numpy.any(numpy.equal(mu, None)):
|
||||
mu = numpy.ones_like(epsilon)
|
||||
|
||||
Dfx, Dfy = operators.deriv_forward(dxes[0])
|
||||
Dbx, Dby = operators.deriv_back(dxes[1])
|
||||
|
||||
eps_parts = numpy.split(epsilon, 3)
|
||||
eps_xy = sparse.diags(numpy.hstack((eps_parts[0], eps_parts[1])))
|
||||
eps_z_inv = sparse.diags(1 / eps_parts[2])
|
||||
|
||||
mu_parts = numpy.split(mu, 3)
|
||||
mu_yx = sparse.diags(numpy.hstack((mu_parts[1], mu_parts[0])))
|
||||
mu_z_inv = sparse.diags(1 / mu_parts[2])
|
||||
|
||||
op = omega * omega * mu_yx @ eps_xy + \
|
||||
mu_yx @ sparse.vstack((-Dby, Dbx)) @ mu_z_inv @ sparse.hstack((-Dfy, Dfx)) + \
|
||||
sparse.vstack((Dfx, Dfy)) @ eps_z_inv @ sparse.hstack((Dbx, Dby)) @ eps_xy
|
||||
return op
|
||||
|
||||
|
||||
def operator_h(omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None,
|
||||
) -> sparse.spmatrix:
|
||||
"""
|
||||
Waveguide operator of the form
|
||||
|
||||
@ -77,7 +51,7 @@ def operator_h(omega: complex,
|
||||
z-dependence is assumed for the fields).
|
||||
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:return: Sparse matrix representation of the operator
|
||||
@ -96,101 +70,51 @@ def operator_h(omega: complex,
|
||||
mu_xy = sparse.diags(numpy.hstack((mu_parts[0], mu_parts[1])))
|
||||
mu_z_inv = sparse.diags(1 / mu_parts[2])
|
||||
|
||||
op = omega * omega * eps_yx @ mu_xy + \
|
||||
op = omega ** 2 * eps_yx @ mu_xy + \
|
||||
eps_yx @ sparse.vstack((-Dfy, Dfx)) @ eps_z_inv @ sparse.hstack((-Dby, Dbx)) + \
|
||||
sparse.vstack((Dbx, Dby)) @ mu_z_inv @ sparse.hstack((Dfx, Dfy)) @ mu_xy
|
||||
|
||||
return op
|
||||
|
||||
|
||||
def normalized_fields_e(e_xy: numpy.ndarray,
|
||||
wavenumber: complex,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None,
|
||||
dx_prop: float = 0,
|
||||
) -> Tuple[vfield_t, vfield_t]:
|
||||
def normalized_fields(v: numpy.ndarray,
|
||||
wavenumber: complex,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None
|
||||
) -> Tuple[vfield_t, vfield_t]:
|
||||
"""
|
||||
Given a vector e_xy containing the vectorized E_x and E_y fields,
|
||||
Given a vector v containing the vectorized H_x and H_y fields,
|
||||
returns normalized, vectorized E and H fields for the system.
|
||||
|
||||
:param e_xy: Vector containing E_x and E_y fields
|
||||
:param wavenumber: Wavenumber satisfying `operator_e(...) @ e_xy == wavenumber**2 * e_xy`
|
||||
:param v: Vector containing H_x and H_y fields
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:param dxes_prop: Grid cell width in the propagation direction. Default 0 (continuous).
|
||||
:return: Normalized, vectorized (e, h) containing all vector components.
|
||||
"""
|
||||
e = exy2e(wavenumber=wavenumber, dxes=dxes, epsilon=epsilon) @ e_xy
|
||||
h = exy2h(wavenumber=wavenumber, omega=omega, dxes=dxes, epsilon=epsilon, mu=mu) @ e_xy
|
||||
e_norm, h_norm = _normalized_fields(e=e, h=h, wavenumber=wavenumber, omega=omega,
|
||||
dxes=dxes, epsilon=epsilon, mu=mu, dx_prop=dx_prop)
|
||||
return e_norm, h_norm
|
||||
e = v2e(v, wavenumber, omega, dxes, epsilon, mu=mu)
|
||||
h = v2h(v, wavenumber, dxes, mu=mu)
|
||||
|
||||
|
||||
def normalized_fields_h(h_xy: numpy.ndarray,
|
||||
wavenumber: complex,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None,
|
||||
dx_prop: float = 0,
|
||||
) -> Tuple[vfield_t, vfield_t]:
|
||||
"""
|
||||
Given a vector e_xy containing the vectorized E_x and E_y fields,
|
||||
returns normalized, vectorized E and H fields for the system.
|
||||
|
||||
:param e_xy: Vector containing E_x and E_y fields
|
||||
:param wavenumber: Wavenumber satisfying `operator_e(...) @ e_xy == wavenumber**2 * e_xy`
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:param dxes_prop: Grid cell width in the propagation direction. Default 0 (continuous).
|
||||
:return: Normalized, vectorized (e, h) containing all vector components.
|
||||
"""
|
||||
e = hxy2e(wavenumber=wavenumber, omega=omega, dxes=dxes, epsilon=epsilon, mu=mu) @ h_xy
|
||||
h = hxy2h(wavenumber=wavenumber, dxes=dxes, mu=mu) @ h_xy
|
||||
e_norm, h_norm = _normalized_fields(e=e, h=h, wavenumber=wavenumber, omega=omega,
|
||||
dxes=dxes, epsilon=epsilon, mu=mu, dx_prop=dx_prop)
|
||||
return e_norm, h_norm
|
||||
|
||||
|
||||
def _normalized_fields(e: numpy.ndarray,
|
||||
h: numpy.ndarray,
|
||||
wavenumber: complex,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None,
|
||||
dx_prop: float = 0,
|
||||
) -> Tuple[vfield_t, vfield_t]:
|
||||
# TODO documentation
|
||||
shape = [s.size for s in dxes[0]]
|
||||
dxes_real = [[numpy.real(d) for d in numpy.meshgrid(*dxes[v], indexing='ij')] for v in (0, 1)]
|
||||
|
||||
E = unvec(e, shape)
|
||||
H = unvec(h, shape)
|
||||
|
||||
phase = numpy.exp(-1j * wavenumber * dx_prop / 2)
|
||||
S1 = E[0] * numpy.conj(H[1] * phase) * dxes_real[0][1] * dxes_real[1][0]
|
||||
S2 = E[1] * numpy.conj(H[0] * phase) * dxes_real[0][0] * dxes_real[1][1]
|
||||
P = numpy.real(S1.sum() - S2.sum())
|
||||
S1 = E[0] * numpy.roll(numpy.conj(H[1]), 1, axis=0) * dxes_real[0][1] * dxes_real[1][0]
|
||||
S2 = E[1] * numpy.roll(numpy.conj(H[0]), 1, axis=1) * dxes_real[0][0] * dxes_real[1][1]
|
||||
S = 0.25 * ((S1 + numpy.roll(S1, 1, axis=0)) -
|
||||
(S2 + numpy.roll(S2, 1, axis=1)))
|
||||
P = 0.5 * numpy.real(S.sum())
|
||||
assert P > 0, 'Found a mode propagating in the wrong direction! P={}'.format(P)
|
||||
|
||||
energy = epsilon * e.conj() * e
|
||||
|
||||
norm_amplitude = 1 / numpy.sqrt(P)
|
||||
norm_angle = -numpy.angle(e[energy.argmax()]) # Will randomly add a negative sign when mode is symmetric
|
||||
|
||||
# Try to break symmetry to assign a consistent sign [experimental]
|
||||
E_weighted = unvec(e * energy * numpy.exp(1j * norm_angle), shape)
|
||||
sign = numpy.sign(E_weighted[:, :max(shape[0]//2, 1), :max(shape[1]//2, 1)].real.sum())
|
||||
|
||||
norm_factor = sign * norm_amplitude * numpy.exp(1j * norm_angle)
|
||||
norm_angle = -numpy.angle(e[e.size//2])
|
||||
norm_factor = norm_amplitude * numpy.exp(1j * norm_angle)
|
||||
|
||||
e *= norm_factor
|
||||
h *= norm_factor
|
||||
@ -198,104 +122,56 @@ def _normalized_fields(e: numpy.ndarray,
|
||||
return e, h
|
||||
|
||||
|
||||
def exy2h(wavenumber: complex,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None
|
||||
) -> sparse.spmatrix:
|
||||
def v2h(v: numpy.ndarray,
|
||||
wavenumber: complex,
|
||||
dxes: dx_lists_t,
|
||||
mu: vfield_t = None
|
||||
) -> vfield_t:
|
||||
"""
|
||||
Operator which transforms the vector e_xy containing the vectorized E_x and E_y fields,
|
||||
into a vectorized H containing all three H components
|
||||
Given a vector v containing the vectorized H_x and H_y fields,
|
||||
returns a vectorized H including all three H components.
|
||||
|
||||
:param wavenumber: Wavenumber satisfying `operator_e(...) @ e_xy == wavenumber**2 * e_xy`
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:param v: Vector containing H_x and H_y fields
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:return: Sparse matrix representing the operator
|
||||
"""
|
||||
e2hop = e2h(wavenumber=wavenumber, omega=omega, dxes=dxes, mu=mu)
|
||||
return e2hop @ exy2e(wavenumber=wavenumber, dxes=dxes, epsilon=epsilon)
|
||||
|
||||
|
||||
def hxy2e(wavenumber: complex,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None
|
||||
) -> sparse.spmatrix:
|
||||
"""
|
||||
Operator which transforms the vector h_xy containing the vectorized H_x and H_y fields,
|
||||
into a vectorized E containing all three E components
|
||||
|
||||
:param wavenumber: Wavenumber satisfying `operator_h(...) @ h_xy == wavenumber**2 * h_xy`
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:return: Sparse matrix representing the operator
|
||||
"""
|
||||
h2eop = h2e(wavenumber=wavenumber, omega=omega, dxes=dxes, epsilon=epsilon)
|
||||
return h2eop @ hxy2h(wavenumber=wavenumber, dxes=dxes, mu=mu)
|
||||
|
||||
|
||||
def hxy2h(wavenumber: complex,
|
||||
dxes: dx_lists_t,
|
||||
mu: vfield_t = None
|
||||
) -> sparse.spmatrix:
|
||||
"""
|
||||
Operator which transforms the vector h_xy containing the vectorized H_x and H_y fields,
|
||||
into a vectorized H containing all three H components
|
||||
|
||||
:param wavenumber: Wavenumber satisfying `operator_h(...) @ h_xy == wavenumber**2 * h_xy`
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:return: Sparse matrix representing the operator
|
||||
:return: Vectorized H field with all vector components
|
||||
"""
|
||||
Dfx, Dfy = operators.deriv_forward(dxes[0])
|
||||
hxy2hz = sparse.hstack((Dfx, Dfy)) / (1j * wavenumber)
|
||||
op = sparse.hstack((Dfx, Dfy))
|
||||
|
||||
if not numpy.any(numpy.equal(mu, None)):
|
||||
mu_parts = numpy.split(mu, 3)
|
||||
mu_xy = sparse.diags(numpy.hstack((mu_parts[0], mu_parts[1])))
|
||||
mu_z_inv = sparse.diags(1 / mu_parts[2])
|
||||
|
||||
hxy2hz = mu_z_inv @ hxy2hz @ mu_xy
|
||||
op = mu_z_inv @ op @ mu_xy
|
||||
|
||||
n_pts = dxes[1][0].size * dxes[1][1].size
|
||||
op = sparse.vstack((sparse.eye(2 * n_pts),
|
||||
hxy2hz))
|
||||
return op
|
||||
w = op @ v / (1j * wavenumber)
|
||||
return numpy.hstack((v, w)).flatten()
|
||||
|
||||
|
||||
def exy2e(wavenumber: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
) -> sparse.spmatrix:
|
||||
def v2e(v: numpy.ndarray,
|
||||
wavenumber: complex,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None
|
||||
) -> vfield_t:
|
||||
"""
|
||||
Operator which transforms the vector e_xy containing the vectorized E_x and E_y fields,
|
||||
into a vectorized E containing all three E components
|
||||
Given a vector v containing the vectorized H_x and H_y fields,
|
||||
returns a vectorized E containing all three E components
|
||||
|
||||
:param wavenumber: Wavenumber satisfying `operator_e(...) @ e_xy == wavenumber**2 * e_xy`
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param v: Vector containing H_x and H_y fields
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:return: Sparse matrix representing the operator
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:return: Vectorized E field with all vector components.
|
||||
"""
|
||||
Dbx, Dby = operators.deriv_back(dxes[1])
|
||||
exy2ez = sparse.hstack((Dbx, Dby)) / (1j * wavenumber)
|
||||
|
||||
if not numpy.any(numpy.equal(epsilon, None)):
|
||||
epsilon_parts = numpy.split(epsilon, 3)
|
||||
epsilon_xy = sparse.diags(numpy.hstack((epsilon_parts[0], epsilon_parts[1])))
|
||||
epsilon_z_inv = sparse.diags(1 / epsilon_parts[2])
|
||||
|
||||
exy2ez = epsilon_z_inv @ exy2ez @ epsilon_xy
|
||||
|
||||
n_pts = dxes[0][0].size * dxes[0][1].size
|
||||
op = sparse.vstack((sparse.eye(2 * n_pts),
|
||||
exy2ez))
|
||||
return op
|
||||
h2eop = h2e(wavenumber, omega, dxes, epsilon)
|
||||
return h2eop @ v2h(v, wavenumber, dxes, mu)
|
||||
|
||||
|
||||
def e2h(wavenumber: complex,
|
||||
@ -309,7 +185,7 @@ def e2h(wavenumber: complex,
|
||||
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:return: Sparse matrix representation of the operator
|
||||
"""
|
||||
@ -330,7 +206,7 @@ def h2e(wavenumber: complex,
|
||||
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:return: Sparse matrix representation of the operator
|
||||
"""
|
||||
@ -343,7 +219,7 @@ def curl_e(wavenumber: complex, dxes: dx_lists_t) -> sparse.spmatrix:
|
||||
Discretized curl operator for use with the waveguide E field.
|
||||
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:return: Sparse matrix representation of the operator
|
||||
"""
|
||||
n = 1
|
||||
@ -360,7 +236,7 @@ def curl_h(wavenumber: complex, dxes: dx_lists_t) -> sparse.spmatrix:
|
||||
Discretized curl operator for use with the waveguide H field.
|
||||
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:return: Sparse matrix representation of the operator
|
||||
"""
|
||||
n = 1
|
||||
@ -385,7 +261,7 @@ def h_err(h: vfield_t,
|
||||
:param h: Vectorized H field
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:return: Relative error norm(OP @ h) / norm(h)
|
||||
@ -416,7 +292,7 @@ def e_err(e: vfield_t,
|
||||
:param e: Vectorized E field
|
||||
:param wavenumber: Wavenumber satisfying A @ v == wavenumber**2 * v
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:param mu: Vectorized magnetic permeability grid (default 1 everywhere)
|
||||
:return: Relative error norm(OP @ e) / norm(e)
|
||||
@ -452,7 +328,7 @@ def cylindrical_operator(omega: complex,
|
||||
theta-dependence is assumed for the fields).
|
||||
|
||||
:param omega: The angular frequency of the system
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types (2D)
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header (2D)
|
||||
:param epsilon: Vectorized dielectric constant grid
|
||||
:param r0: Radius of curvature for the simulation. This should be the minimum value of
|
||||
r within the simulation domain.
|
@ -2,53 +2,63 @@ from typing import Dict, List
|
||||
import numpy
|
||||
import scipy.sparse as sparse
|
||||
|
||||
from .. import vec, unvec, dx_lists_t, vfield_t, field_t
|
||||
from . import vec, unvec, dx_lists_t, vfield_t, field_t
|
||||
from . import operators, waveguide, functional
|
||||
from ..eigensolvers import signed_eigensolve, rayleigh_quotient_iteration
|
||||
from .eigensolvers import signed_eigensolve, rayleigh_quotient_iteration
|
||||
|
||||
|
||||
def solve_waveguide_mode_2d(mode_number: int,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: field_t,
|
||||
mu: field_t = None,
|
||||
mode_margin: int = 2,
|
||||
epsilon: vfield_t,
|
||||
mu: vfield_t = None,
|
||||
wavenumber_correction: bool = True,
|
||||
) -> Dict[str, complex or field_t]:
|
||||
"""
|
||||
Given a 2d region, attempts to solve for the eigenmode with the specified mode number.
|
||||
|
||||
:param mode_number: Number of the mode, 0-indexed.
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param epsilon: Dielectric constant
|
||||
:param mu: Magnetic permeability (default 1 everywhere)
|
||||
:param mode_margin: The eigensolver will actually solve for (mode_number + mode_margin)
|
||||
modes, but only return the target mode. Increasing this value can improve the solver's
|
||||
ability to find the correct mode. Default 2.
|
||||
:return: {'E': numpy.ndarray, 'H': numpy.ndarray, 'wavenumber': complex}
|
||||
:param wavenumber_correction: Whether to correct the wavenumber to
|
||||
account for numerical dispersion (default True)
|
||||
:return: {'E': List[numpy.ndarray], 'H': List[numpy.ndarray], 'wavenumber': complex}
|
||||
"""
|
||||
|
||||
'''
|
||||
Solve for the largest-magnitude eigenvalue of the real operator
|
||||
'''
|
||||
dxes_real = [[numpy.real(dx) for dx in dxi] for dxi in dxes]
|
||||
A_r = waveguide.operator_e(numpy.real(omega), dxes_real, vec(numpy.real(epsilon)), vec(numpy.real(mu)))
|
||||
A_r = waveguide.operator(numpy.real(omega), dxes_real, numpy.real(epsilon), numpy.real(mu))
|
||||
|
||||
eigvals, eigvecs = signed_eigensolve(A_r, mode_number + mode_margin)
|
||||
exy = eigvecs[:, -(mode_number + 1)]
|
||||
eigvals, eigvecs = signed_eigensolve(A_r, mode_number+3)
|
||||
v = eigvecs[:, -(mode_number + 1)]
|
||||
|
||||
'''
|
||||
Now solve for the eigenvector of the full operator, using the real operator's
|
||||
eigenvector as an initial guess for Rayleigh quotient iteration.
|
||||
'''
|
||||
A = waveguide.operator_e(omega, dxes, vec(epsilon), vec(mu))
|
||||
eigval, exy = rayleigh_quotient_iteration(A, exy)
|
||||
A = waveguide.operator(omega, dxes, epsilon, mu)
|
||||
eigval, v = rayleigh_quotient_iteration(A, v)
|
||||
|
||||
# Calculate the wave-vector (force the real part to be positive)
|
||||
wavenumber = numpy.sqrt(eigval)
|
||||
wavenumber *= numpy.sign(numpy.real(wavenumber))
|
||||
|
||||
e, h = waveguide.normalized_fields_e(exy, wavenumber, omega, dxes, vec(epsilon), vec(mu))
|
||||
e, h = waveguide.normalized_fields(v, wavenumber, omega, dxes, epsilon, mu)
|
||||
|
||||
'''
|
||||
Perform correction on wavenumber to account for numerical dispersion.
|
||||
|
||||
See Numerical Dispersion in Taflove's FDTD book.
|
||||
This correction term reduces the error in emitted power, but additional
|
||||
error is introduced into the E_err and H_err terms. This effect becomes
|
||||
more pronounced as beta increases.
|
||||
'''
|
||||
if wavenumber_correction:
|
||||
wavenumber -= 2 * numpy.sin(numpy.real(wavenumber / 2)) - numpy.real(wavenumber)
|
||||
|
||||
shape = [d.size for d in dxes[0]]
|
||||
fields = {
|
||||
@ -68,6 +78,7 @@ def solve_waveguide_mode(mode_number: int,
|
||||
slices: List[slice],
|
||||
epsilon: field_t,
|
||||
mu: field_t = None,
|
||||
wavenumber_correction: bool = True
|
||||
) -> Dict[str, complex or numpy.ndarray]:
|
||||
"""
|
||||
Given a 3D grid, selects a slice from the grid and attempts to
|
||||
@ -75,19 +86,19 @@ def solve_waveguide_mode(mode_number: int,
|
||||
|
||||
:param mode_number: Number of the mode, 0-indexed
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param axis: Propagation axis (0=x, 1=y, 2=z)
|
||||
:param polarity: Propagation direction (+1 for +ve, -1 for -ve)
|
||||
:param slices: epsilon[tuple(slices)] is used to select the portion of the grid to use
|
||||
as the waveguide cross-section. slices[axis] should select only one
|
||||
:param epsilon: Dielectric constant
|
||||
:param mu: Magnetic permeability (default 1 everywhere)
|
||||
:param wavenumber_correction: Whether to correct the wavenumber to
|
||||
account for numerical dispersion (default True)
|
||||
:return: {'E': List[numpy.ndarray], 'H': List[numpy.ndarray], 'wavenumber': complex}
|
||||
"""
|
||||
if mu is None:
|
||||
mu = numpy.ones_like(epsilon)
|
||||
|
||||
slices = tuple(slices)
|
||||
mu = [numpy.ones_like(epsilon[0])] * 3
|
||||
|
||||
'''
|
||||
Solve the 2D problem in the specified plane
|
||||
@ -96,54 +107,57 @@ def solve_waveguide_mode(mode_number: int,
|
||||
order = numpy.roll(range(3), 2 - axis)
|
||||
reverse_order = numpy.roll(range(3), axis - 2)
|
||||
|
||||
# Find dx in propagation direction
|
||||
dxab_forward = numpy.array([dx[order[2]][slices[order[2]]] for dx in dxes])
|
||||
dx_prop = 0.5 * sum(dxab_forward)
|
||||
|
||||
# Reduce to 2D and solve the 2D problem
|
||||
args_2d = {
|
||||
'dxes': [[dx[i][slices[i]] for i in order[:2]] for dx in dxes],
|
||||
'epsilon': [epsilon[i][slices].transpose(order) for i in order],
|
||||
'mu': [mu[i][slices].transpose(order) for i in order],
|
||||
'epsilon': vec([epsilon[i][slices].transpose(order) for i in order]),
|
||||
'mu': vec([mu[i][slices].transpose(order) for i in order]),
|
||||
'wavenumber_correction': wavenumber_correction,
|
||||
}
|
||||
fields_2d = solve_waveguide_mode_2d(mode_number, omega=omega, **args_2d)
|
||||
|
||||
'''
|
||||
Apply corrections and expand to 3D
|
||||
'''
|
||||
# Correct wavenumber to account for numerical dispersion.
|
||||
fields_2d['wavenumber'] = 2/dx_prop * numpy.arcsin(fields_2d['wavenumber'] * dx_prop/2)
|
||||
# Scale based on dx in propagation direction
|
||||
dxab_forward = numpy.array([dx[order[2]][slices[order[2]]] for dx in dxes])
|
||||
|
||||
# Adjust for propagation direction
|
||||
fields_2d['H'] *= polarity
|
||||
fields_2d['E'][2] *= polarity
|
||||
fields_2d['H'][2] *= polarity
|
||||
|
||||
# Apply phase shift to H-field
|
||||
fields_2d['H'][:2] *= numpy.exp(-1j * polarity * 0.5 * fields_2d['wavenumber'] * dx_prop)
|
||||
fields_2d['E'][2] *= numpy.exp(-1j * polarity * 0.5 * fields_2d['wavenumber'] * dx_prop)
|
||||
d_prop = 0.5 * sum(dxab_forward)
|
||||
for a in range(3):
|
||||
fields_2d['H'][a] *= numpy.exp(-polarity * 1j * 0.5 * fields_2d['wavenumber'] * d_prop)
|
||||
|
||||
# Expand E, H to full epsilon space we were given
|
||||
E = numpy.zeros_like(epsilon, dtype=complex)
|
||||
H = numpy.zeros_like(epsilon, dtype=complex)
|
||||
E = [None]*3
|
||||
H = [None]*3
|
||||
for a, o in enumerate(reverse_order):
|
||||
E[(a, *slices)] = fields_2d['E'][o][:, :, None].transpose(reverse_order)
|
||||
H[(a, *slices)] = fields_2d['H'][o][:, :, None].transpose(reverse_order)
|
||||
E[a] = numpy.zeros_like(epsilon[0], dtype=complex)
|
||||
H[a] = numpy.zeros_like(epsilon[0], dtype=complex)
|
||||
|
||||
E[a][slices] = fields_2d['E'][o][:, :, None].transpose(reverse_order)
|
||||
H[a][slices] = fields_2d['H'][o][:, :, None].transpose(reverse_order)
|
||||
|
||||
results = {
|
||||
'wavenumber': fields_2d['wavenumber'],
|
||||
'H': H,
|
||||
'E': E,
|
||||
}
|
||||
|
||||
return results
|
||||
|
||||
|
||||
def compute_source(E: field_t,
|
||||
H: field_t,
|
||||
wavenumber: complex,
|
||||
omega: complex,
|
||||
dxes: dx_lists_t,
|
||||
axis: int,
|
||||
polarity: int,
|
||||
slices: List[slice],
|
||||
epsilon: field_t,
|
||||
mu: field_t = None,
|
||||
) -> field_t:
|
||||
"""
|
||||
@ -151,9 +165,10 @@ def compute_source(E: field_t,
|
||||
necessary to position a unidirectional source at the slice location.
|
||||
|
||||
:param E: E-field of the mode
|
||||
:param H: H-field of the mode (advanced by half of a Yee cell from E)
|
||||
:param wavenumber: Wavenumber of the mode
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param axis: Propagation axis (0=x, 1=y, 2=z)
|
||||
:param polarity: Propagation direction (+1 for +ve, -1 for -ve)
|
||||
:param slices: epsilon[tuple(slices)] is used to select the portion of the grid to use
|
||||
@ -161,20 +176,28 @@ def compute_source(E: field_t,
|
||||
:param mu: Magnetic permeability (default 1 everywhere)
|
||||
:return: J distribution for the unidirectional source
|
||||
"""
|
||||
E_expanded = expand_wgmode_e(E=E, dxes=dxes, wavenumber=wavenumber, axis=axis,
|
||||
polarity=polarity, slices=slices)
|
||||
if mu is None:
|
||||
mu = [1] * 3
|
||||
|
||||
smask = [slice(None)] * 4
|
||||
if polarity > 0:
|
||||
smask[axis + 1] = slice(slices[axis].start, None)
|
||||
else:
|
||||
smask[axis + 1] = slice(None, slices[axis].stop)
|
||||
J = [None]*3
|
||||
M = [None]*3
|
||||
|
||||
mask = numpy.zeros_like(E_expanded, dtype=int)
|
||||
mask[tuple(smask)] = 1
|
||||
src_order = numpy.roll(range(3), axis)
|
||||
exp_iphi = numpy.exp(1j * polarity * wavenumber * dxes[1][axis][slices[axis]])
|
||||
J[src_order[0]] = numpy.zeros_like(E[0])
|
||||
J[src_order[1]] = +exp_iphi * H[src_order[2]] * polarity
|
||||
J[src_order[2]] = -exp_iphi * H[src_order[1]] * polarity
|
||||
|
||||
M[src_order[0]] = numpy.zeros_like(E[0])
|
||||
M[src_order[1]] = +numpy.roll(E[src_order[2]], -1, axis=axis)
|
||||
M[src_order[2]] = -numpy.roll(E[src_order[1]], -1, axis=axis)
|
||||
|
||||
A1f = functional.curl_h(dxes)
|
||||
|
||||
Jm_iw = A1f([M[k] / mu[k] for k in range(3)])
|
||||
for k in range(3):
|
||||
J[k] += Jm_iw[k] / (-1j * omega)
|
||||
|
||||
masked_e2j = operators.e_boundary_source(mask=vec(mask), omega=omega, dxes=dxes, epsilon=vec(epsilon), mu=vec(mu))
|
||||
J = unvec(masked_e2j @ vec(E_expanded), E.shape[1:])
|
||||
return J
|
||||
|
||||
|
||||
@ -186,7 +209,6 @@ def compute_overlap_e(E: field_t,
|
||||
axis: int,
|
||||
polarity: int,
|
||||
slices: List[slice],
|
||||
epsilon: field_t, # TODO unused??
|
||||
mu: field_t = None,
|
||||
) -> field_t:
|
||||
"""
|
||||
@ -201,7 +223,7 @@ def compute_overlap_e(E: field_t,
|
||||
:param H: H-field of the mode (advanced by half of a Yee cell from E)
|
||||
:param wavenumber: Wavenumber of the mode
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header
|
||||
:param axis: Propagation axis (0=x, 1=y, 2=z)
|
||||
:param polarity: Propagation direction (+1 for +ve, -1 for -ve)
|
||||
:param slices: epsilon[tuple(slices)] is used to select the portion of the grid to use
|
||||
@ -209,11 +231,8 @@ def compute_overlap_e(E: field_t,
|
||||
:param mu: Magnetic permeability (default 1 everywhere)
|
||||
:return: overlap_e for calculating the mode overlap
|
||||
"""
|
||||
slices = tuple(slices)
|
||||
|
||||
cross_plane = [slice(None)] * 4
|
||||
cross_plane[axis + 1] = slices[axis]
|
||||
cross_plane = tuple(cross_plane)
|
||||
cross_plane = [slice(None)] * 3
|
||||
cross_plane[axis] = slices[axis]
|
||||
|
||||
# Determine phase factors for parallel slices
|
||||
a_shape = numpy.roll([-1, 1, 1], axis)
|
||||
@ -224,8 +243,11 @@ def compute_overlap_e(E: field_t,
|
||||
phase_H = numpy.exp(iphi * (a_H - a_H[slices[axis]])).reshape(a_shape)
|
||||
|
||||
# Expand our slice to the entire grid using the calculated phase factors
|
||||
Ee = phase_E * E[cross_plane]
|
||||
He = phase_H * H[cross_plane]
|
||||
Ee = [None]*3
|
||||
He = [None]*3
|
||||
for k in range(3):
|
||||
Ee[k] = phase_E * E[k][tuple(cross_plane)]
|
||||
He[k] = phase_H * H[k][tuple(cross_plane)]
|
||||
|
||||
|
||||
# Write out the operator product for the mode orthogonality integral
|
||||
@ -257,19 +279,21 @@ def solve_waveguide_mode_cylindrical(mode_number: int,
|
||||
dxes: dx_lists_t,
|
||||
epsilon: vfield_t,
|
||||
r0: float,
|
||||
wavenumber_correction: bool = True,
|
||||
) -> Dict[str, complex or field_t]:
|
||||
"""
|
||||
TODO: fixup
|
||||
Given a 2d (r, y) slice of epsilon, attempts to solve for the eigenmode
|
||||
of the bent waveguide with the specified mode number.
|
||||
|
||||
:param mode_number: Number of the mode, 0-indexed
|
||||
:param omega: Angular frequency of the simulation
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types.
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in fdfd_tools.operators header.
|
||||
The first coordinate is assumed to be r, the second is y.
|
||||
:param epsilon: Dielectric constant
|
||||
:param r0: Radius of curvature for the simulation. This should be the minimum value of
|
||||
r within the simulation domain.
|
||||
:param wavenumber_correction: Whether to correct the wavenumber to
|
||||
account for numerical dispersion (default True)
|
||||
:return: {'E': List[numpy.ndarray], 'H': List[numpy.ndarray], 'wavenumber': complex}
|
||||
"""
|
||||
|
||||
@ -293,7 +317,16 @@ def solve_waveguide_mode_cylindrical(mode_number: int,
|
||||
wavenumber = numpy.sqrt(eigval)
|
||||
wavenumber *= numpy.sign(numpy.real(wavenumber))
|
||||
|
||||
# TODO: Perform correction on wavenumber to account for numerical dispersion.
|
||||
'''
|
||||
Perform correction on wavenumber to account for numerical dispersion.
|
||||
|
||||
See Numerical Dispersion in Taflove's FDTD book.
|
||||
This correction term reduces the error in emitted power, but additional
|
||||
error is introduced into the E_err and H_err terms. This effect becomes
|
||||
more pronounced as the wavenumber increases.
|
||||
'''
|
||||
if wavenumber_correction:
|
||||
wavenumber -= 2 * numpy.sin(numpy.real(wavenumber / 2)) - numpy.real(wavenumber)
|
||||
|
||||
shape = [d.size for d in dxes[0]]
|
||||
v = numpy.hstack((v, numpy.zeros(shape[0] * shape[1])))
|
||||
@ -305,60 +338,3 @@ def solve_waveguide_mode_cylindrical(mode_number: int,
|
||||
}
|
||||
|
||||
return fields
|
||||
|
||||
|
||||
def compute_overlap_ce(E: field_t,
|
||||
wavenumber: complex,
|
||||
dxes: dx_lists_t,
|
||||
axis: int,
|
||||
polarity: int,
|
||||
slices: List[slice],
|
||||
) -> field_t:
|
||||
slices = tuple(slices)
|
||||
|
||||
Ee = expand_wgmode_e(E=E, wavenumber=wavenumber,
|
||||
dxes=dxes, axis=axis, polarity=polarity,
|
||||
slices=slices)
|
||||
|
||||
start, stop = sorted((slices[axis].start, slices[axis].start - 2 * polarity))
|
||||
|
||||
slices2 = list(slices)
|
||||
slices2[axis] = slice(start, stop)
|
||||
slices2 = (slice(None), *slices2)
|
||||
|
||||
Etgt = numpy.zeros_like(Ee)
|
||||
Etgt[slices2] = Ee[slices2]
|
||||
|
||||
Etgt /= (Etgt.conj() * Etgt).sum()
|
||||
return Etgt, slices2
|
||||
|
||||
|
||||
def expand_wgmode_e(E: field_t,
|
||||
wavenumber: complex,
|
||||
dxes: dx_lists_t,
|
||||
axis: int,
|
||||
polarity: int,
|
||||
slices: List[slice],
|
||||
) -> field_t:
|
||||
slices = tuple(slices)
|
||||
|
||||
# Determine phase factors for parallel slices
|
||||
a_shape = numpy.roll([1, -1, 1, 1], axis)
|
||||
a_E = numpy.real(dxes[0][axis]).cumsum()
|
||||
r_E = a_E - a_E[slices[axis]]
|
||||
iphi = polarity * -1j * wavenumber
|
||||
phase_E = numpy.exp(iphi * r_E).reshape(a_shape)
|
||||
|
||||
# Expand our slice to the entire grid using the phase factors
|
||||
E_expanded = numpy.zeros_like(E)
|
||||
|
||||
slices_exp = list(slices)
|
||||
slices_exp[axis] = slice(E.shape[axis + 1])
|
||||
slices_exp = (slice(None), *slices_exp)
|
||||
|
||||
slices_in = (slice(None), *slices)
|
||||
|
||||
E_expanded[slices_exp] = phase_E * numpy.array(E)[slices_in]
|
||||
return E_expanded
|
||||
|
||||
|
@ -1,48 +0,0 @@
|
||||
"""
|
||||
Electromagnetic simulation tools
|
||||
|
||||
This package is intended for building simulation inputs, analyzing
|
||||
simulation outputs, and running short simulations on unspecialized hardware.
|
||||
It is designed to provide tooling and a baseline for other, high-performance
|
||||
purpose- and hardware-specific solvers.
|
||||
|
||||
|
||||
**Contents**
|
||||
- Finite difference frequency domain (FDFD)
|
||||
* Library of sparse matrices for representing the electromagnetic wave
|
||||
equation in 3D, as well as auxiliary matrices for conversion between fields
|
||||
* Waveguide mode operators
|
||||
* Waveguide mode eigensolver
|
||||
* Stretched-coordinate PML boundaries (SCPML)
|
||||
* Functional versions of most operators
|
||||
* Anisotropic media (limited to diagonal elements eps_xx, eps_yy, eps_zz, mu_xx, ...)
|
||||
* Arbitrary distributions of perfect electric and magnetic conductors (PEC / PMC)
|
||||
- Finite difference time domain (FDTD)
|
||||
* Basic Maxwell time-steps
|
||||
* Poynting vector and energy calculation
|
||||
* Convolutional PMLs
|
||||
|
||||
This package does *not* provide a fast matrix solver, though by default
|
||||
```meanas.fdfd.solvers.generic(...)``` will call
|
||||
```scipy.sparse.linalg.qmr(...)``` to perform a solve.
|
||||
For 2D FDFD problems this should be fine; likewise, the waveguide mode
|
||||
solver uses scipy's eigenvalue solver, with reasonable results.
|
||||
|
||||
For solving large (or 3D) FDFD problems, I recommend a GPU-based iterative
|
||||
solver, such as [opencl_fdfd](https://mpxd.net/code/jan/opencl_fdfd) or
|
||||
those included in [MAGMA](http://icl.cs.utk.edu/magma/index.html)). Your
|
||||
solver will need the ability to solve complex symmetric (non-Hermitian)
|
||||
linear systems, ideally with double precision.
|
||||
|
||||
|
||||
Dependencies:
|
||||
- numpy
|
||||
- scipy
|
||||
|
||||
"""
|
||||
|
||||
from .types import dx_lists_t, field_t, vfield_t, field_updater
|
||||
from .vectorization import vec, unvec
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
version = '0.5'
|
@ -1,9 +0,0 @@
|
||||
"""
|
||||
Basic FDTD functionality
|
||||
"""
|
||||
|
||||
from .base import maxwell_e, maxwell_h
|
||||
from .pml import cpml
|
||||
from .energy import (poynting, poynting_divergence, energy_hstep, energy_estep,
|
||||
delta_energy_h2e, delta_energy_h2e, delta_energy_j)
|
||||
from .boundaries import conducting_boundary
|
@ -1,87 +0,0 @@
|
||||
"""
|
||||
Basic FDTD field updates
|
||||
"""
|
||||
from typing import List, Callable, Tuple, Dict
|
||||
import numpy
|
||||
|
||||
from .. import dx_lists_t, field_t, field_updater
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
|
||||
|
||||
def curl_h(dxes: dx_lists_t = None) -> field_updater:
|
||||
"""
|
||||
Curl operator for use with the H field.
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:return: Function for taking the discretized curl of the H-field, F(H) -> curlH
|
||||
"""
|
||||
if dxes:
|
||||
dxyz_b = numpy.meshgrid(*dxes[1], indexing='ij')
|
||||
|
||||
def dh(f, ax):
|
||||
return (f - numpy.roll(f, 1, axis=ax)) / dxyz_b[ax]
|
||||
else:
|
||||
def dh(f, ax):
|
||||
return f - numpy.roll(f, 1, axis=ax)
|
||||
|
||||
def ch_fun(h: field_t) -> field_t:
|
||||
output = numpy.empty_like(h)
|
||||
output[0] = dh(h[2], 1)
|
||||
output[1] = dh(h[0], 2)
|
||||
output[2] = dh(h[1], 0)
|
||||
output[0] -= dh(h[1], 2)
|
||||
output[1] -= dh(h[2], 0)
|
||||
output[2] -= dh(h[0], 1)
|
||||
return output
|
||||
|
||||
return ch_fun
|
||||
|
||||
|
||||
def curl_e(dxes: dx_lists_t = None) -> field_updater:
|
||||
"""
|
||||
Curl operator for use with the E field.
|
||||
|
||||
:param dxes: Grid parameters [dx_e, dx_h] as described in meanas.types
|
||||
:return: Function for taking the discretized curl of the E-field, F(E) -> curlE
|
||||
"""
|
||||
if dxes is not None:
|
||||
dxyz_a = numpy.meshgrid(*dxes[0], indexing='ij')
|
||||
|
||||
def de(f, ax):
|
||||
return (numpy.roll(f, -1, axis=ax) - f) / dxyz_a[ax]
|
||||
else:
|
||||
def de(f, ax):
|
||||
return numpy.roll(f, -1, axis=ax) - f
|
||||
|
||||
def ce_fun(e: field_t) -> field_t:
|
||||
output = numpy.empty_like(e)
|
||||
output[0] = de(e[2], 1)
|
||||
output[1] = de(e[0], 2)
|
||||
output[2] = de(e[1], 0)
|
||||
output[0] -= de(e[1], 2)
|
||||
output[1] -= de(e[2], 0)
|
||||
output[2] -= de(e[0], 1)
|
||||
return output
|
||||
|
||||
return ce_fun
|
||||
|
||||
|
||||
def maxwell_e(dt: float, dxes: dx_lists_t = None) -> field_updater:
|
||||
curl_h_fun = curl_h(dxes)
|
||||
|
||||
def me_fun(e: field_t, h: field_t, epsilon: field_t):
|
||||
e += dt * curl_h_fun(h) / epsilon
|
||||
return e
|
||||
|
||||
return me_fun
|
||||
|
||||
|
||||
def maxwell_h(dt: float, dxes: dx_lists_t = None) -> field_updater:
|
||||
curl_e_fun = curl_e(dxes)
|
||||
|
||||
def mh_fun(e: field_t, h: field_t):
|
||||
h -= dt * curl_e_fun(e)
|
||||
return h
|
||||
|
||||
return mh_fun
|
@ -1,68 +0,0 @@
|
||||
"""
|
||||
Boundary conditions
|
||||
"""
|
||||
|
||||
from typing import List, Callable, Tuple, Dict
|
||||
import numpy
|
||||
|
||||
from .. import dx_lists_t, field_t, field_updater
|
||||
|
||||
|
||||
def conducting_boundary(direction: int,
|
||||
polarity: int
|
||||
) -> Tuple[field_updater, field_updater]:
|
||||
dirs = [0, 1, 2]
|
||||
if direction not in dirs:
|
||||
raise Exception('Invalid direction: {}'.format(direction))
|
||||
dirs.remove(direction)
|
||||
u, v = dirs
|
||||
|
||||
if polarity < 0:
|
||||
boundary_slice = [slice(None)] * 3
|
||||
shifted1_slice = [slice(None)] * 3
|
||||
boundary_slice[direction] = 0
|
||||
shifted1_slice[direction] = 1
|
||||
|
||||
def en(e: field_t):
|
||||
e[direction][boundary_slice] = 0
|
||||
e[u][boundary_slice] = e[u][shifted1_slice]
|
||||
e[v][boundary_slice] = e[v][shifted1_slice]
|
||||
return e
|
||||
|
||||
def hn(h: field_t):
|
||||
h[direction][boundary_slice] = h[direction][shifted1_slice]
|
||||
h[u][boundary_slice] = 0
|
||||
h[v][boundary_slice] = 0
|
||||
return h
|
||||
|
||||
return en, hn
|
||||
|
||||
elif polarity > 0:
|
||||
boundary_slice = [slice(None)] * 3
|
||||
shifted1_slice = [slice(None)] * 3
|
||||
shifted2_slice = [slice(None)] * 3
|
||||
boundary_slice[direction] = -1
|
||||
shifted1_slice[direction] = -2
|
||||
shifted2_slice[direction] = -3
|
||||
|
||||
def ep(e: field_t):
|
||||
e[direction][boundary_slice] = -e[direction][shifted2_slice]
|
||||
e[direction][shifted1_slice] = 0
|
||||
e[u][boundary_slice] = e[u][shifted1_slice]
|
||||
e[v][boundary_slice] = e[v][shifted1_slice]
|
||||
return e
|
||||
|
||||
def hp(h: field_t):
|
||||
h[direction][boundary_slice] = h[direction][shifted1_slice]
|
||||
h[u][boundary_slice] = -h[u][shifted2_slice]
|
||||
h[u][shifted1_slice] = 0
|
||||
h[v][boundary_slice] = -h[v][shifted2_slice]
|
||||
h[v][shifted1_slice] = 0
|
||||
return h
|
||||
|
||||
return ep, hp
|
||||
|
||||
else:
|
||||
raise Exception('Bad polarity: {}'.format(polarity))
|
||||
|
||||
|
@ -1,84 +0,0 @@
|
||||
from typing import List, Callable, Tuple, Dict
|
||||
import numpy
|
||||
|
||||
from .. import dx_lists_t, field_t, field_updater
|
||||
|
||||
|
||||
def poynting(e, h):
|
||||
s = (numpy.roll(e[1], -1, axis=0) * h[2] - numpy.roll(e[2], -1, axis=0) * h[1],
|
||||
numpy.roll(e[2], -1, axis=1) * h[0] - numpy.roll(e[0], -1, axis=1) * h[2],
|
||||
numpy.roll(e[0], -1, axis=2) * h[1] - numpy.roll(e[1], -1, axis=2) * h[0])
|
||||
return numpy.array(s)
|
||||
|
||||
|
||||
def poynting_divergence(s=None, *, e=None, h=None, dxes=None): # TODO dxes
|
||||
if dxes is None:
|
||||
dxes = tuple(tuple(numpy.ones(1) for _ in range(3)) for _ in range(2))
|
||||
|
||||
if s is None:
|
||||
s = poynting(e, h)
|
||||
|
||||
ds = ((s[0] - numpy.roll(s[0], 1, axis=0)) / numpy.sqrt(dxes[0][0] * dxes[1][0])[:, None, None] +
|
||||
(s[1] - numpy.roll(s[1], 1, axis=1)) / numpy.sqrt(dxes[0][1] * dxes[1][1])[None, :, None] +
|
||||
(s[2] - numpy.roll(s[2], 1, axis=2)) / numpy.sqrt(dxes[0][2] * dxes[1][2])[None, None, :] )
|
||||
return ds
|
||||
|
||||
|
||||
def energy_hstep(e0, h1, e2, epsilon=None, mu=None, dxes=None):
|
||||
u = dxmul(e0 * e2, h1 * h1, epsilon, mu, dxes)
|
||||
return u
|
||||
|
||||
|
||||
def energy_estep(h0, e1, h2, epsilon=None, mu=None, dxes=None):
|
||||
u = dxmul(e1 * e1, h0 * h2, epsilon, mu, dxes)
|
||||
return u
|
||||
|
||||
|
||||
def delta_energy_h2e(dt, e0, h1, e2, h3, epsilon=None, mu=None, dxes=None):
|
||||
"""
|
||||
This is just from (e2 * e2 + h3 * h1) - (h1 * h1 + e0 * e2)
|
||||
"""
|
||||
de = e2 * (e2 - e0) / dt
|
||||
dh = h1 * (h3 - h1) / dt
|
||||
du = dxmul(de, dh, epsilon, mu, dxes)
|
||||
return du
|
||||
|
||||
|
||||
def delta_energy_e2h(dt, h0, e1, h2, e3, epsilon=None, mu=None, dxes=None):
|
||||
"""
|
||||
This is just from (h2 * h2 + e3 * e1) - (e1 * e1 + h0 * h2)
|
||||
"""
|
||||
de = e1 * (e3 - e1) / dt
|
||||
dh = h2 * (h2 - h0) / dt
|
||||
du = dxmul(de, dh, epsilon, mu, dxes)
|
||||
return du
|
||||
|
||||
|
||||
def delta_energy_j(j0, e1, dxes=None):
|
||||
if dxes is None:
|
||||
dxes = tuple(tuple(numpy.ones(1) for _ in range(3)) for _ in range(2))
|
||||
|
||||
du = ((j0 * e1).sum(axis=0) *
|
||||
dxes[0][0][:, None, None] *
|
||||
dxes[0][1][None, :, None] *
|
||||
dxes[0][2][None, None, :])
|
||||
return du
|
||||
|
||||
|
||||
def dxmul(ee, hh, epsilon=None, mu=None, dxes=None):
|
||||
if epsilon is None:
|
||||
epsilon = 1
|
||||
if mu is None:
|
||||
mu = 1
|
||||
if dxes is None:
|
||||
dxes = tuple(tuple(numpy.ones(1) for _ in range(3)) for _ in range(2))
|
||||
|
||||
result = ((ee * epsilon).sum(axis=0) *
|
||||
dxes[0][0][:, None, None] *
|
||||
dxes[0][1][None, :, None] *
|
||||
dxes[0][2][None, None, :] +
|
||||
(hh * mu).sum(axis=0) *
|
||||
dxes[1][0][:, None, None] *
|
||||
dxes[1][1][None, :, None] *
|
||||
dxes[1][2][None, None, :])
|
||||
return result
|
@ -1,122 +0,0 @@
|
||||
"""
|
||||
PML implementations
|
||||
|
||||
"""
|
||||
# TODO retest pmls!
|
||||
|
||||
from typing import List, Callable, Tuple, Dict
|
||||
import numpy
|
||||
|
||||
from .. import dx_lists_t, field_t, field_updater
|
||||
|
||||
|
||||
__author__ = 'Jan Petykiewicz'
|
||||
|
||||
|
||||
def cpml(direction:int,
|
||||
polarity: int,
|
||||
dt: float,
|
||||
epsilon: field_t,
|
||||
thickness: int = 8,
|
||||
ln_R_per_layer: float = -1.6,
|
||||
epsilon_eff: float = 1,
|
||||
mu_eff: float = 1,
|
||||
m: float = 3.5,
|
||||
ma: float = 1,
|
||||
cfs_alpha: float = 0,
|
||||
dtype: numpy.dtype = numpy.float32,
|
||||
) -> Tuple[Callable, Callable, Dict[str, field_t]]:
|
||||
|
||||
if direction not in range(3):
|
||||
raise Exception('Invalid direction: {}'.format(direction))
|
||||
|
||||
if polarity not in (-1, 1):
|
||||
raise Exception('Invalid polarity: {}'.format(polarity))
|
||||
|
||||
if thickness <= 2:
|
||||
raise Exception('It would be wise to have a pml with 4+ cells of thickness')
|
||||
|
||||
if epsilon_eff <= 0:
|
||||
raise Exception('epsilon_eff must be positive')
|
||||
|
||||
sigma_max = -ln_R_per_layer / 2 * (m + 1)
|
||||
kappa_max = numpy.sqrt(epsilon_eff * mu_eff)
|
||||
alpha_max = cfs_alpha
|
||||
transverse = numpy.delete(range(3), direction)
|
||||
u, v = transverse
|
||||
|
||||
xe = numpy.arange(1, thickness+1, dtype=float)
|
||||
xh = numpy.arange(1, thickness+1, dtype=float)
|
||||
if polarity > 0:
|
||||
xe -= 0.5
|
||||
elif polarity < 0:
|
||||
xh -= 0.5
|
||||
xe = xe[::-1]
|
||||
xh = xh[::-1]
|
||||
else:
|
||||
raise Exception('Bad polarity!')
|
||||
|
||||
expand_slice = [None] * 3
|
||||
expand_slice[direction] = slice(None)
|
||||
|
||||
def par(x):
|
||||
scaling = (x / thickness) ** m
|
||||
sigma = scaling * sigma_max
|
||||
kappa = 1 + scaling * (kappa_max - 1)
|
||||
alpha = ((1 - x / thickness) ** ma) * alpha_max
|
||||
p0 = numpy.exp(-(sigma / kappa + alpha) * dt)
|
||||
p1 = sigma / (sigma + kappa * alpha) * (p0 - 1)
|
||||
p2 = 1 / kappa
|
||||
return p0[expand_slice], p1[expand_slice], p2[expand_slice]
|
||||
|
||||
p0e, p1e, p2e = par(xe)
|
||||
p0h, p1h, p2h = par(xh)
|
||||
|
||||
region = [slice(None)] * 3
|
||||
if polarity < 0:
|
||||
region[direction] = slice(None, thickness)
|
||||
elif polarity > 0:
|
||||
region[direction] = slice(-thickness, None)
|
||||
else:
|
||||
raise Exception('Bad polarity!')
|
||||
|
||||
se = 1 if direction == 1 else -1
|
||||
|
||||
# TODO check if epsilon is uniform in pml region?
|
||||
shape = list(epsilon[0].shape)
|
||||
shape[direction] = thickness
|
||||
psi_e = [numpy.zeros(shape, dtype=dtype), numpy.zeros(shape, dtype=dtype)]
|
||||
psi_h = [numpy.zeros(shape, dtype=dtype), numpy.zeros(shape, dtype=dtype)]
|
||||
|
||||
fields = {
|
||||
'psi_e_u': psi_e[0],
|
||||
'psi_e_v': psi_e[1],
|
||||
'psi_h_u': psi_h[0],
|
||||
'psi_h_v': psi_h[1],
|
||||
}
|
||||
|
||||
# Note that this is kinda slow -- would be faster to reuse dHv*p2h for the original
|
||||
# H update, but then you have multiple arrays and a monolithic (field + pml) update operation
|
||||
def pml_e(e: field_t, h: field_t, epsilon: field_t) -> Tuple[field_t, field_t]:
|
||||
dHv = h[v][region] - numpy.roll(h[v], 1, axis=direction)[region]
|
||||
dHu = h[u][region] - numpy.roll(h[u], 1, axis=direction)[region]
|
||||
psi_e[0] *= p0e
|
||||
psi_e[0] += p1e * dHv * p2e
|
||||
psi_e[1] *= p0e
|
||||
psi_e[1] += p1e * dHu * p2e
|
||||
e[u][region] += se * dt / epsilon[u][region] * (psi_e[0] + (p2e - 1) * dHv)
|
||||
e[v][region] -= se * dt / epsilon[v][region] * (psi_e[1] + (p2e - 1) * dHu)
|
||||
return e, h
|
||||
|
||||
def pml_h(e: field_t, h: field_t) -> Tuple[field_t, field_t]:
|
||||
dEv = (numpy.roll(e[v], -1, axis=direction)[region] - e[v][region])
|
||||
dEu = (numpy.roll(e[u], -1, axis=direction)[region] - e[u][region])
|
||||
psi_h[0] *= p0h
|
||||
psi_h[0] += p1h * dEv * p2h
|
||||
psi_h[1] *= p0h
|
||||
psi_h[1] += p1h * dEu * p2h
|
||||
h[u][region] -= se * dt * (psi_h[0] + (p2h - 1) * dEv)
|
||||
h[v][region] += se * dt * (psi_h[1] + (p2h - 1) * dEu)
|
||||
return e, h
|
||||
|
||||
return pml_e, pml_h, fields
|
@ -1,293 +0,0 @@
|
||||
import numpy
|
||||
import pytest
|
||||
import dataclasses
|
||||
from typing import List, Tuple
|
||||
from numpy.testing import assert_allclose, assert_array_equal
|
||||
|
||||
from meanas import fdtd
|
||||
|
||||
|
||||
prng = numpy.random.RandomState(12345)
|
||||
|
||||
|
||||
def assert_fields_close(a, b, *args, **kwargs):
|
||||
numpy.testing.assert_allclose(a, b, verbose=False, err_msg='Fields did not match:\n{}\n{}'.format(numpy.rollaxis(a, -1),
|
||||
numpy.rollaxis(b, -1)), *args, **kwargs)
|
||||
|
||||
def assert_close(a, b, *args, **kwargs):
|
||||
numpy.testing.assert_allclose(a, b, *args, **kwargs)
|
||||
|
||||
|
||||
def test_initial_fields(sim):
|
||||
# Make sure initial fields didn't change
|
||||
e0 = sim.es[0]
|
||||
h0 = sim.hs[0]
|
||||
j0 = sim.js[0]
|
||||
mask = (j0 != 0)
|
||||
|
||||
assert_fields_close(e0[mask], j0[mask] / sim.epsilon[mask])
|
||||
assert not e0[~mask].any()
|
||||
assert not h0.any()
|
||||
|
||||
|
||||
def test_initial_energy(sim):
|
||||
"""
|
||||
Assumes fields start at 0 before J0 is added
|
||||
"""
|
||||
j0 = sim.js[0]
|
||||
e0 = sim.es[0]
|
||||
h0 = sim.hs[0]
|
||||
h1 = sim.hs[1]
|
||||
mask = (j0 != 0)
|
||||
dV = numpy.prod(numpy.meshgrid(*sim.dxes[0], indexing='ij'), axis=0)
|
||||
u0 = (j0 * j0.conj() / sim.epsilon * dV).sum(axis=0)
|
||||
args = {'dxes': sim.dxes,
|
||||
'epsilon': sim.epsilon}
|
||||
|
||||
# Make sure initial energy and E dot J are correct
|
||||
energy0 = fdtd.energy_estep(h0=h0, e1=e0, h2=h1, **args)
|
||||
e0_dot_j0 = fdtd.delta_energy_j(j0=j0, e1=e0, dxes=sim.dxes)
|
||||
assert_fields_close(energy0, u0)
|
||||
assert_fields_close(e0_dot_j0, u0)
|
||||
|
||||
|
||||
def test_energy_conservation(sim):
|
||||
"""
|
||||
Assumes fields start at 0 before J0 is added
|
||||
"""
|
||||
e0 = sim.es[0]
|
||||
j0 = sim.js[0]
|
||||
u = fdtd.delta_energy_j(j0=j0, e1=e0, dxes=sim.dxes).sum()
|
||||
args = {'dxes': sim.dxes,
|
||||
'epsilon': sim.epsilon}
|
||||
|
||||
for ii in range(1, 8):
|
||||
u_hstep = fdtd.energy_hstep(e0=sim.es[ii-1], h1=sim.hs[ii], e2=sim.es[ii], **args)
|
||||
u_estep = fdtd.energy_estep(h0=sim.hs[ii], e1=sim.es[ii], h2=sim.hs[ii + 1], **args)
|
||||
delta_j_A = fdtd.delta_energy_j(j0=sim.js[ii], e1=sim.es[ii-1], dxes=sim.dxes)
|
||||
delta_j_B = fdtd.delta_energy_j(j0=sim.js[ii], e1=sim.es[ii], dxes=sim.dxes)
|
||||
|
||||
u += delta_j_A.sum()
|
||||
assert_close(u_hstep.sum(), u)
|
||||
u += delta_j_B.sum()
|
||||
assert_close(u_estep.sum(), u)
|
||||
|
||||
|
||||
def test_poynting_divergence(sim):
|
||||
args = {'dxes': sim.dxes,
|
||||
'epsilon': sim.epsilon}
|
||||
|
||||
dV = numpy.prod(numpy.meshgrid(*sim.dxes[0], indexing='ij'), axis=0)
|
||||
|
||||
u_eprev = None
|
||||
for ii in range(1, 8):
|
||||
u_hstep = fdtd.energy_hstep(e0=sim.es[ii-1], h1=sim.hs[ii], e2=sim.es[ii], **args)
|
||||
u_estep = fdtd.energy_estep(h0=sim.hs[ii], e1=sim.es[ii], h2=sim.hs[ii + 1], **args)
|
||||
delta_j_B = fdtd.delta_energy_j(j0=sim.js[ii], e1=sim.es[ii], dxes=sim.dxes)
|
||||
|
||||
du_half_h2e = u_estep - u_hstep - delta_j_B
|
||||
div_s_h2e = sim.dt * fdtd.poynting_divergence(e=sim.es[ii], h=sim.hs[ii], dxes=sim.dxes) * dV
|
||||
assert_fields_close(du_half_h2e, -div_s_h2e)
|
||||
|
||||
if u_eprev is None:
|
||||
u_eprev = u_estep
|
||||
continue
|
||||
|
||||
# previous half-step
|
||||
delta_j_A = fdtd.delta_energy_j(j0=sim.js[ii], e1=sim.es[ii-1], dxes=sim.dxes)
|
||||
|
||||
du_half_e2h = u_hstep - u_eprev - delta_j_A
|
||||
div_s_e2h = sim.dt * fdtd.poynting_divergence(e=sim.es[ii-1], h=sim.hs[ii], dxes=sim.dxes) * dV
|
||||
assert_fields_close(du_half_e2h, -div_s_e2h)
|
||||
u_eprev = u_estep
|
||||
|
||||
|
||||
def test_poynting_planes(sim):
|
||||
mask = (sim.js[0] != 0)
|
||||
if mask.sum() > 1:
|
||||
pytest.skip('test_poynting_planes can only test single point sources')
|
||||
|
||||
args = {'dxes': sim.dxes,
|
||||
'epsilon': sim.epsilon}
|
||||
dV = numpy.prod(numpy.meshgrid(*sim.dxes[0], indexing='ij'), axis=0)
|
||||
|
||||
mx = numpy.roll(mask, (-1, -1), axis=(0, 1))
|
||||
my = numpy.roll(mask, -1, axis=2)
|
||||
mz = numpy.roll(mask, (+1, -1), axis=(0, 3))
|
||||
px = numpy.roll(mask, -1, axis=0)
|
||||
py = mask.copy()
|
||||
pz = numpy.roll(mask, +1, axis=0)
|
||||
|
||||
u_eprev = None
|
||||
for ii in range(1, 8):
|
||||
u_hstep = fdtd.energy_hstep(e0=sim.es[ii-1], h1=sim.hs[ii], e2=sim.es[ii], **args)
|
||||
u_estep = fdtd.energy_estep(h0=sim.hs[ii], e1=sim.es[ii], h2=sim.hs[ii + 1], **args)
|
||||
|
||||
s_h2e = -fdtd.poynting(e=sim.es[ii], h=sim.hs[ii]) * sim.dt
|
||||
s_h2e[0] *= sim.dxes[0][1][None, :, None] * sim.dxes[0][2][None, None, :]
|
||||
s_h2e[1] *= sim.dxes[0][0][:, None, None] * sim.dxes[0][2][None, None, :]
|
||||
s_h2e[2] *= sim.dxes[0][0][:, None, None] * sim.dxes[0][1][None, :, None]
|
||||
planes = [s_h2e[px].sum(), -s_h2e[mx].sum(),
|
||||
s_h2e[py].sum(), -s_h2e[my].sum(),
|
||||
s_h2e[pz].sum(), -s_h2e[mz].sum()]
|
||||
assert_close(sum(planes), (u_estep - u_hstep).sum())
|
||||
if u_eprev is None:
|
||||
u_eprev = u_estep
|
||||
continue
|
||||
|
||||
s_e2h = -fdtd.poynting(e=sim.es[ii - 1], h=sim.hs[ii]) * sim.dt
|
||||
s_e2h[0] *= sim.dxes[0][1][None, :, None] * sim.dxes[0][2][None, None, :]
|
||||
s_e2h[1] *= sim.dxes[0][0][:, None, None] * sim.dxes[0][2][None, None, :]
|
||||
s_e2h[2] *= sim.dxes[0][0][:, None, None] * sim.dxes[0][1][None, :, None]
|
||||
planes = [s_e2h[px].sum(), -s_e2h[mx].sum(),
|
||||
s_e2h[py].sum(), -s_e2h[my].sum(),
|
||||
s_e2h[pz].sum(), -s_e2h[mz].sum()]
|
||||
assert_close(sum(planes), (u_hstep - u_eprev).sum())
|
||||
|
||||
# previous half-step
|
||||
u_eprev = u_estep
|
||||
|
||||
|
||||
#####################################
|
||||
# Test fixtures
|
||||
#####################################
|
||||
|
||||
@pytest.fixture(scope='module',
|
||||
params=[(5, 5, 1),
|
||||
(5, 1, 5),
|
||||
(5, 5, 5),
|
||||
# (7, 7, 7),
|
||||
])
|
||||
def shape(request):
|
||||
yield (3, *request.param)
|
||||
|
||||
|
||||
@pytest.fixture(scope='module', params=[0.3])
|
||||
def dt(request):
|
||||
yield request.param
|
||||
|
||||
|
||||
@pytest.fixture(scope='module', params=[1.0, 1.5])
|
||||
def epsilon_bg(request):
|
||||
yield request.param
|
||||
|
||||
|
||||
@pytest.fixture(scope='module', params=[1.0, 2.5])
|
||||
def epsilon_fg(request):
|
||||
yield request.param
|
||||
|
||||
|
||||
@pytest.fixture(scope='module', params=['center', '000', 'random'])
|
||||
def epsilon(request, shape, epsilon_bg, epsilon_fg):
|
||||
is3d = (numpy.array(shape) == 1).sum() == 0
|
||||
if is3d:
|
||||
if request.param == '000':
|
||||
pytest.skip('Skipping 000 epsilon because test is 3D (for speed)')
|
||||
if epsilon_bg != 1:
|
||||
pytest.skip('Skipping epsilon_bg != 1 because test is 3D (for speed)')
|
||||
if epsilon_fg not in (1.0, 2.0):
|
||||
pytest.skip('Skipping epsilon_fg not in (1, 2) because test is 3D (for speed)')
|
||||
|
||||
epsilon = numpy.full(shape, epsilon_bg, dtype=float)
|
||||
if request.param == 'center':
|
||||
epsilon[:, shape[1]//2, shape[2]//2, shape[3]//2] = epsilon_fg
|
||||
elif request.param == '000':
|
||||
epsilon[:, 0, 0, 0] = epsilon_fg
|
||||
elif request.param == 'random':
|
||||
epsilon[:] = prng.uniform(low=min(epsilon_bg, epsilon_fg),
|
||||
high=max(epsilon_bg, epsilon_fg),
|
||||
size=shape)
|
||||
|
||||
yield epsilon
|
||||
|
||||
|
||||
@pytest.fixture(scope='module', params=[1.0])#, 1.5])
|
||||
def j_mag(request):
|
||||
yield request.param
|
||||
|
||||
|
||||
@pytest.fixture(scope='module', params=['center', 'random'])
|
||||
def j_distribution(request, shape, j_mag):
|
||||
j = numpy.zeros(shape)
|
||||
if request.param == 'center':
|
||||
j[:, shape[1]//2, shape[2]//2, shape[3]//2] = j_mag
|
||||
elif request.param == '000':
|
||||
j[:, 0, 0, 0] = j_mag
|
||||
elif request.param == 'random':
|
||||
j[:] = prng.uniform(low=-j_mag, high=j_mag, size=shape)
|
||||
yield j
|
||||
|
||||
|
||||
@pytest.fixture(scope='module', params=[1.0, 1.5])
|
||||
def dx(request):
|
||||
yield request.param
|
||||
|
||||
|
||||
@pytest.fixture(scope='module', params=['uniform'])
|
||||
def dxes(request, shape, dx):
|
||||
if request.param == 'uniform':
|
||||
dxes = [[numpy.full(s, dx) for s in shape[1:]] for _ in range(2)]
|
||||
yield dxes
|
||||
|
||||
|
||||
@pytest.fixture(scope='module',
|
||||
params=[(0,),
|
||||
(0, 4, 8),
|
||||
]
|
||||
)
|
||||
def j_steps(request):
|
||||
yield request.param
|
||||
|
||||
|
||||
@dataclasses.dataclass()
|
||||
class SimResult:
|
||||
shape: Tuple[int]
|
||||
dt: float
|
||||
dxes: List[List[numpy.ndarray]]
|
||||
epsilon: numpy.ndarray
|
||||
j_distribution: numpy.ndarray
|
||||
j_steps: Tuple[int]
|
||||
es: List[numpy.ndarray] = dataclasses.field(default_factory=list)
|
||||
hs: List[numpy.ndarray] = dataclasses.field(default_factory=list)
|
||||
js: List[numpy.ndarray] = dataclasses.field(default_factory=list)
|
||||
|
||||
|
||||
@pytest.fixture(scope='module')
|
||||
def sim(request, shape, epsilon, dxes, dt, j_distribution, j_steps):
|
||||
is3d = (numpy.array(shape) == 1).sum() == 0
|
||||
if is3d:
|
||||
if dt != 0.3:
|
||||
pytest.skip('Skipping dt != 0.3 because test is 3D (for speed)')
|
||||
|
||||
sim = SimResult(
|
||||
shape=shape,
|
||||
dt=dt,
|
||||
dxes=dxes,
|
||||
epsilon=epsilon,
|
||||
j_distribution=j_distribution,
|
||||
j_steps=j_steps,
|
||||
)
|
||||
|
||||
e = numpy.zeros_like(epsilon)
|
||||
h = numpy.zeros_like(epsilon)
|
||||
|
||||
assert 0 in j_steps
|
||||
j_zeros = numpy.zeros_like(j_distribution)
|
||||
|
||||
eh2h = fdtd.maxwell_h(dt=dt, dxes=dxes)
|
||||
eh2e = fdtd.maxwell_e(dt=dt, dxes=dxes)
|
||||
for tt in range(10):
|
||||
e = e.copy()
|
||||
h = h.copy()
|
||||
eh2h(e, h)
|
||||
eh2e(e, h, epsilon)
|
||||
if tt in j_steps:
|
||||
e += j_distribution / epsilon
|
||||
sim.js.append(j_distribution)
|
||||
else:
|
||||
sim.js.append(j_zeros)
|
||||
sim.es.append(e)
|
||||
sim.hs.append(h)
|
||||
return sim
|
||||
|
||||
|
@ -1,22 +0,0 @@
|
||||
"""
|
||||
Types shared across multiple submodules
|
||||
"""
|
||||
import numpy
|
||||
from typing import List, Callable
|
||||
|
||||
|
||||
# Field types
|
||||
field_t = numpy.ndarray # vector field with shape (3, X, Y, Z) (e.g. [E_x, E_y, E_z])
|
||||
vfield_t = numpy.ndarray # linearized vector field (vector of length 3*X*Y*Z)
|
||||
|
||||
'''
|
||||
'dxes' datastructure which contains grid cell width information in the following format:
|
||||
[[[dx_e_0, dx_e_1, ...], [dy_e_0, ...], [dz_e_0, ...]],
|
||||
[[dx_h_0, dx_h_1, ...], [dy_h_0, ...], [dz_h_0, ...]]]
|
||||
where dx_e_0 is the x-width of the x=0 cells, as used when calculating dE/dx,
|
||||
and dy_h_0 is the y-width of the y=0 cells, as used when calculating dH/dy, etc.
|
||||
'''
|
||||
dx_lists_t = List[List[numpy.ndarray]]
|
||||
|
||||
|
||||
field_updater = Callable[[field_t], field_t]
|
28
setup.py
28
setup.py
@ -1,36 +1,18 @@
|
||||
#!/usr/bin/env python3
|
||||
#!/usr/bin/env python
|
||||
|
||||
from setuptools import setup, find_packages
|
||||
import meanas
|
||||
|
||||
with open('README.md', 'r') as f:
|
||||
long_description = f.read()
|
||||
|
||||
setup(name='meanas',
|
||||
version=meanas.version,
|
||||
description='Electromagnetic simulation tools',
|
||||
long_description=long_description,
|
||||
long_description_content_type='text/markdown',
|
||||
setup(name='fdfd_tools',
|
||||
version='0.4',
|
||||
description='FDFD Electromagnetic simulation tools',
|
||||
author='Jan Petykiewicz',
|
||||
author_email='anewusername@gmail.com',
|
||||
url='https://mpxd.net/code/jan/fdfd_tools',
|
||||
url='https://mpxd.net/gogs/jan/fdfd_tools',
|
||||
packages=find_packages(),
|
||||
install_requires=[
|
||||
'numpy',
|
||||
'scipy',
|
||||
],
|
||||
extras_require={
|
||||
'test': [
|
||||
'pytest',
|
||||
'dataclasses',
|
||||
],
|
||||
},
|
||||
classifiers=[
|
||||
'Programming Language :: Python :: 3',
|
||||
'Development Status :: 4 - Beta',
|
||||
'Intended Audience :: Developers',
|
||||
'Intended Audience :: Science/Research',
|
||||
'License :: OSI Approved :: GNU Affero General Public License v3',
|
||||
'Topic :: Scientific/Engineering :: Physics',
|
||||
],
|
||||
)
|
||||
|
Loading…
Reference in New Issue
Block a user