From 49132118837d12bac3c5d509a9d32d233abb812a Mon Sep 17 00:00:00 2001
From: Jan Petykiewicz <jan@mpxd.net>
Date: Fri, 17 Apr 2026 19:29:33 -0700
Subject: [PATCH] [fdfd.eme] fix abcd array construction

---
 meanas/fdfd/eme.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/meanas/fdfd/eme.py b/meanas/fdfd/eme.py
index f834973..cb1b99e 100644
--- a/meanas/fdfd/eme.py
+++ b/meanas/fdfd/eme.py
@@ -55,7 +55,13 @@ def get_abcd(
     B = r21 @ t21i
     C = -t21i @ r12
     D = t21i
-    return sparse.block_array(((A, B), (C, D)))
+    return sparse.block_array(
+        [
+            [sparse.csr_array(A), sparse.csr_array(B)],
+            [sparse.csr_array(C), sparse.csr_array(D)],
+            ],
+        format='csr',
+        )
 
 
 def get_s(