# HG changeset patch
# User jwe
# Date 1173974692 0
# Node ID 250eebbd7cccdf43b0ae0337d6b498cfc0c6303f
# Parent  cf8e671beada393ac9e171ff2b5588b29b1a15c8
[project @ 2007-03-15 16:04:52 by jwe]

diff -r cf8e671beada -r 250eebbd7ccc liboctave/ChangeLog
--- a/liboctave/ChangeLog	Thu Mar 15 14:11:51 2007 +0000
+++ b/liboctave/ChangeLog	Thu Mar 15 16:04:52 2007 +0000
@@ -1,3 +1,8 @@
+2007-03-15  John W. Eaton  <jwe@octave.org>
+
+	* lo-mappers.cc (acos): Use formula similar to what we use for asin.
+	From Alexander Barth <abarth@marine.usf.edu>.
+
 2007-03-12  John W. Eaton  <jwe@octave.org>
 
 	* oct-inttypes.h (octave_int::octave_int (double)):
diff -r cf8e671beada -r 250eebbd7ccc liboctave/lo-mappers.cc
--- a/liboctave/lo-mappers.cc	Thu Mar 15 14:11:51 2007 +0000
+++ b/liboctave/lo-mappers.cc	Thu Mar 15 16:04:52 2007 +0000
@@ -209,7 +209,7 @@
 {
   static Complex i (0, 1);
 
-  return (real (x) * imag (x) < 0.0) ? i * acosh (x) : -i * acosh (x);
+  return -i * (log (x + i * (sqrt (1.0 - x*x))));
 }
 
 Complex