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Re: [Q]: ID analog to FORTRAN "sign" function



Rostyslav Pavlichenko wrote:

> Does the IDl have something close to Fortran SIGN (DSIGN... so on...)
> functions
> 
> IN FORTRAN:
> Elemental Intrinsic Function (Generic):
> Returns the absolute value of the first argument times the sign of the
> second argument.
> 
> Syntax:
> =======
> result = SIGN (a, b)
>         a  (Input) Must be of type integer or real.
> 
>         b  Must have the same type and kind parameters as a.
> 
> Results:
> =========
> The result type is the same as a.
> The value of the result is
> | a | if b >= zero
> and -| a | if b < zero.

No, but you can easily write it:

function sign, a, b
  if ( b ge 0 ) then $
    return, abs( a ) $
  else $
    return, -abs( a )
end

It works for both integer and float data types

        Alex
-- 
  Alex Schuster     Wonko@weird.cologne.de          PGP Key available
                    alex@pet.mpin-koeln.mpg.de