changeset 14767:d213da1a16a6

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).
author Rik <octave@nomad.inbox5.com>
date Thu, 14 Jun 2012 08:35:05 -0700
parents 877263efaacc
children 1c7956c661a8
files libcruft/slatec-fn/derf.f
diffstat 1 files changed, 1 insertions(+), 1 deletions(-) [+]
line wrap: on
line diff
--- 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