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Workaround for the Legendre function bug in scipy #181

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Workaround for the Legendre function bug in scipy #181

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5 changes: 4 additions & 1 deletion spharpy/special.py
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Original file line number Diff line number Diff line change
Expand Up @@ -392,10 +392,13 @@ def legendre_function(n, m, z, cs_phase=True):
"""
z = np.atleast_1d(z)

if m == 0:
legendre = _spspecial.eval_legendre(n, z) # This is reliable
else:
# squeeze required because the legendre function introduced in scipy 1.15
# returns a 2D array, whereas the previous function `lpmn` returned a 1D
# array
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@ahms5 ahms5 Sep 17, 2025

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Suggested change
# squeeze required because the legendre function introduced in scipy 1.15
# returns a 2D array, whereas the previous function `lpmn` returned a 1D
# array
# squeeze required because the legendre function introduced in scipy 1.15
# returns a 2D array, whereas the previous function `lpmn` returned a 1D
# array

legendre = np.squeeze(_spspecial.assoc_legendre_p(n, m, z))
legendre = np.squeeze(_spspecial.assoc_legendre_p(n, m, z))

# remove Condon-Shortley phase
if not cs_phase and m % 2:
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