commit 57239f4a8149dbd603ad376e90a0a4574b846710
author Till Hoffmann <tillahoffmann@gmail.com> Fri Apr 01 14:35:21 2016 +0100
committer Till Hoffmann <tillahoffmann@gmail.com> Fri Apr 01 14:35:21 2016 +0100
tree 4ff7041da6cd7121c19271bfb385c813ea66e0a8
parent dd5d390daf3a3a561a772b64f1b602e5f240bf8b

Added polygamma function.

test/array.cpp

diff --git a/test/array.cpp b/test/array.cpp
index 2f0b0f1..56d1969 100644
--- a/test/array.cpp
+++ b/test/array.cpp
@@ -331,6 +331,11 @@
     VERIFY_IS_APPROX(numext::zeta(Scalar(3), Scalar(-2.5)), RealScalar(0.054102025820864097));
     VERIFY_IS_EQUAL(numext::zeta(Scalar(1), Scalar(1.2345)), // The second scalar does not matter
                     std::numeric_limits<RealScalar>::infinity());
+    
+    // Check the polygamma against scipy.special.polygamma
+    VERIFY_IS_APPROX(numext::polygamma(Scalar(1), Scalar(2)), RealScalar(0.644934066848));
+    VERIFY_IS_APPROX(numext::polygamma(Scalar(1), Scalar(3)), RealScalar(0.394934066848));
+    VERIFY_IS_APPROX(numext::polygamma(Scalar(1), Scalar(25.5)), RealScalar(0.0399946696496));
 
     {
       // Test various propreties of igamma & igammac.  These are normalized