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Re: [gfortran] Implement irand(), rand(), and srand() for G77 compatibility


On Sun, May 30, 2004 at 11:10:20PM +0100, Paul Brook wrote:
> On Sunday 30 May 2004 19:55, Steve Kargl wrote:
> 
> > GFC_REAL_4 prefix(rand) (GFC_INTEGER_4 *i)
> > {
> >   return (GFC_REAL_4) (prefix(irand)(i) - 1) / (GFC_REAL_4)(GFC_RAND_M1);
> > }
> 
> This returns values in the range [0,1]
> We really need a reliable routine to convert from integer to real.
> 

Nothing like a 3rd followup message.  The original code is okay.

irand(i) returns a value in the range [1,GFC_RAND_M-1].
irand(i) - 1 is in the range [0,GFC_RAND_M-2].  So, the
division above is in the range [0,1).

-- 
Steve


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