[Bug fortran/51569] documentation on sign intrinsic

[kargl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51569

kargl at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |FIXED

--- Comment #4 from kargl at gcc dot gnu.org 2012-01-15 18:03:05 UTC ---
(In reply to comment #0)
> The documentation of the sign intrinsic is a bit misleading when the B argument
> is a signed zero. The explanation in the standard is much more clearer.
> 
> Currently it says
> (http://gcc.gnu.org/onlinedocs/gcc-4.6.2/gfortran/SIGN.html#SIGN):
> "If B\ge 0 then the result is ABS(A), else it is -ABS(A)."
> 
> According to the standard -0.0 is greater than zero. Meaning that according to
> the documentation I would expect:
> sign(1.0,-0.0) = 1.0
> which is not true.
> 
> I would replace the sentence above by what you can find in the standard:

The documentation as written is fine.  It seems that you
are reading 'B \ge 0' in gfortran's documentation as a 
Fortran expression instead of as a mathematical expression.
>From the point of view of mathematics if B = -0., then
B is less than 0.; otherwise, the foundations of calculus
would not apply when taking a limit of a function at 0.
Closing as WONTFIX.