Merge pull request #141 from dkazanc/defrag-radway-79

Optimize `calc_filter` (LPRec)

Author: dkazanc

tests/test_fourier.py

@@ -0,0 +1,26 @@
+from tomobar.fourier import calc_filter
+from numpy.testing import assert_allclose
+import pytest
+
+
+@pytest.mark.parametrize(
+    "test_case",
+    [
+        ("none", 100),
+        ("ramp", 0.496701),
+        ("shepp", 0.447188),
+        ("cosine", 0.25168),
+        ("cosine2", 0.164889),
+        ("hamming", 0.185245),
+        ("hann", 0.164889),
+        ("parzen", 0.042508),
+    ],
+)
+def test_calc_filter(test_case):
+    filter_name, expected_median = test_case
+    length = 100
+    f = calc_filter(length, filter_name, 1.0)
+    assert f.size == length / 2 + 1
+    f = f.get()
+    f.sort()
+    assert_allclose(f[f.size // 2], expected_median, rtol=1e-5)

tomobar/fourier.py

@@ -100,9 +100,7 @@ def _wint(n, t):
     for j in range(N - n + 1):
         # Change coordinates, and constant and linear parts
         W = ((t[j + n - 1] - t[j]) ** 2) * W1 + (t[j + n - 1] - t[j]) * t[j] * W2
-
-        for k in range(n - 1):
-            w[j : j + n] = w[j : j + n] + p[j + k] * W[:, k]
+        w[j : j + n] += W @ p[j : j + n - 1]
 
     wn = w
     wn[-40:] = (w[-40]) / (N - 40) * np.arange(N - 40, N)