fix: spreading function with s not an integer

4Subsea · Sep 27, 2022 · c9c097d · c9c097d
1 parent 6ecd3ef
commit c9c097d
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Showing 2 changed files with 4 additions and 2 deletions.
diff --git a/src/waveresponse/_core.py b/src/waveresponse/_core.py
@@ -1424,7 +1424,7 @@ def _spread_fun(self, _, theta, /):
 
         s = self._s
         c = 2 ** (2 * s + 1) * gamma(s + 1) ** 2 / gamma(2 * s + 1)
-        return c * np.cos(theta) ** (2.0 * s)
+        return c * (np.cos(theta) ** 2.0) ** s
 
 
 class CosineFullSpreading(BaseSpreading):
@@ -1465,4 +1465,4 @@ def __init__(self, s=1, degrees=False):
     def _spread_fun(self, _, theta, /):
         s = self._s
         c = 2 ** (2 * s) * gamma(s + 1) ** 2 / gamma(2 * s + 1)
-        return c * np.cos(theta / 2.0) ** (2.0 * s)
+        return c * (np.cos(theta / 2.0) ** 2.0) ** s
diff --git a/tests/test_core.py b/tests/test_core.py
@@ -3149,6 +3149,7 @@ def test__init__(self):
         [0, 45, 2, 0.005396691782172398],
         [0, -45, 2, 0.005396691782172398],
         [0, 45 + 2 * 360, 2, 0.005396691782172398],
+        [0, 359, 0.5, 0.004363156988011003],
     ]
 
     @pytest.mark.parametrize("f,d,s,spread_expect", params__call__degrees)
@@ -3178,6 +3179,7 @@ def test__call__degrees(self, f, d, s, spread_expect):
         [0, np.pi / 4, 2, 0.309207662451413],
         [0, -np.pi / 4, 2, 0.309207662451413],
         [0, np.pi / 4 + 2 * 2.0 * np.pi, 2, 0.309207662451413],
+        [0, 7 * np.pi / 4.0, 0.5, 0.23096988312782166],
     ]
 
     @pytest.mark.parametrize("f,d,s,spread_expect", params__call__radians)