# HG changeset patch
# User Michael Godfrey <michaeldgodfrey@gmail.com>
# Date 1361070419 18000
# Node ID 7cfb186592deb3afd2d7ee823a029187ab4aeba3
# Parent  821922270b66c35c6953c4441b36a24a8da573c0
Make signbit return logical 0 or 1 (bug #38291)

* libinterp/corefcn/mappers.cc(Fsignbit): Return logical
value (xsignbit != 0).

diff -r 821922270b66 -r 7cfb186592de libinterp/corefcn/mappers.cc
--- a/libinterp/corefcn/mappers.cc	Wed Feb 20 14:58:39 2013 -0800
+++ b/libinterp/corefcn/mappers.cc	Sat Feb 16 22:06:59 2013 -0500
@@ -1882,7 +1882,10 @@
 DEFUNX ("signbit", Fsignbit, args, ,
     "-*- texinfo -*-\n\
 @deftypefn {Mapping Function} {} signbit (@var{x})\n\
-Return a nonzero value if the value of @var{x} has its sign bit set.\n\
+Return logical true if the value of @var{x} has its sign bit set.\n\
+Otherwise return logical false.  This behavior is consistent with the other\n\
+logical functions. See@ref{Logical Values}.  The behavior differs from the\n\
+C language function which returns non-zero if the sign bit is set.\n\
 \n\
 This is not the same as @code{x < 0.0}, because IEEE 754 floating point\n\
 allows zero to be signed.  The comparison @code{-0.0 < 0.0} is false,\n\
@@ -1891,8 +1894,9 @@
 @end deftypefn")
 {
   octave_value retval;
-  if (args.length () == 1)
+  if (args.length () == 1) {
     retval = args(0).xsignbit ();
+    retval = (retval != 0); }
   else
     print_usage ();