# HG changeset patch
# User Rik <octave@nomad.inbox5.com>
# Date 1339688105 25200
# Node ID d213da1a16a6ed0823057eb92df607d187c9608c
# Parent  877263efaacc303eb0f9b75c56d5f68bde62195a
Correct Fortran implementation of erf for small values (Bug #36364)

* derf.f: For small values approximation to erf should be 2*x/sqrt(pi),
not 2*x*x/sqrt(pi).

diff -r 877263efaacc -r d213da1a16a6 libcruft/slatec-fn/derf.f
--- a/libcruft/slatec-fn/derf.f	Wed Jun 13 14:10:45 2012 -0700
+++ b/libcruft/slatec-fn/derf.f	Thu Jun 14 08:35:05 2012 -0700
@@ -69,7 +69,7 @@
 C
 C ERF(X) = 1.0 - ERFC(X)  FOR  -1.0 .LE. X .LE. 1.0
 C
-      IF (Y.LE.SQEPS) DERF = 2.0D0*X*X/SQRTPI
+      IF (Y.LE.SQEPS) DERF = 2.0D0*X/SQRTPI
       IF (Y.GT.SQEPS) DERF = X*(1.0D0 + DCSEVL (2.D0*X*X-1.D0,
      1  ERFCS, NTERF))
       RETURN