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109 lines
2.6 KiB
Python
109 lines
2.6 KiB
Python
import numpy
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from numpy.linalg import norm
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import pyopencl
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import pyopencl.array
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import time
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from . import ops
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class CSRMatrix(object):
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row_ptr = None # type: pyopencl.array.Array
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col_ind = None # type: pyopencl.array.Array
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data = None # type: pyopencl.array.Array
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def __init__(self, queue, m):
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self.row_ptr = pyopencl.array.to_device(queue, m.indptr)
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self.col_ind = pyopencl.array.to_device(queue, m.indices)
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self.data = pyopencl.array.to_device(queue, m.data.astype(numpy.complex128))
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def cg(a, b, max_iters=10000, err_thresh=1e-6, context=None, queue=None, verbose=False):
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start_time = time.perf_counter()
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if context is None:
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context = pyopencl.create_some_context(False)
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if queue is None:
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queue = pyopencl.CommandQueue(context)
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def load_field(v, dtype=numpy.complex128):
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return pyopencl.array.to_device(queue, v.astype(dtype))
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r = load_field(b)
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x = pyopencl.array.zeros_like(r)
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v = pyopencl.array.zeros_like(r)
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p = pyopencl.array.zeros_like(r)
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alpha = 1.0 + 0j
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rho = 1.0 + 0j
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errs = []
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m = CSRMatrix(queue, a)
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'''
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Generate OpenCL kernels
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'''
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a_step = ops.create_a_csr(context)
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xr_step = ops.create_xr_step(context)
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rhoerr_step = ops.create_rhoerr_step(context)
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p_step = ops.create_p_step(context)
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dot = ops.create_dot(context)
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'''
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Start the solve
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'''
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start_time2 = time.perf_counter()
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_, err2 = rhoerr_step(r, [])
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b_norm = numpy.sqrt(err2)
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print('b_norm check: ', b_norm)
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success = False
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for k in range(max_iters):
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if verbose:
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print('[{:06d}] rho {:.4} alpha {:4.4}'.format(k, rho, alpha), end=' ')
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rho_prev = rho
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e = xr_step(x, p, r, v, alpha, [])
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rho, err2 = rhoerr_step(r, e)
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errs += [numpy.sqrt(err2) / b_norm]
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if verbose:
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print('err', errs[-1])
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if errs[-1] < err_thresh:
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success = True
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break
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e = p_step(p, r, rho/rho_prev, [])
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e = a_step(v, m, p, e)
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alpha = rho / dot(p, v, e)
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if k % 1000 == 0:
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print(k)
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'''
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Done solving
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'''
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time_elapsed = time.perf_counter() - start_time
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x = x.get()
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if success:
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print('Success', end='')
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else:
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print('Failure', end=', ')
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print(', {} iterations in {} sec: {} iterations/sec \
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'.format(k, time_elapsed, k / time_elapsed))
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print('final error', errs[-1])
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print('overhead {} sec'.format(start_time2 - start_time))
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print('Post-everything residual:', norm(a @ x - b) / norm(b))
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return x
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