[GRASS5] TODOs for 5.0.0

Glynn Clements glynn.clements at virgin.net
Fri Aug 31 19:47:02 EDT 2001


Markus Neteler wrote:

> > + rand1 - Used by r.surf.fractal, r.surf.gauss, r.surf.random.
> > 
> > Free PRNGs are readily available; the most obvious candidates are:
> > 
> > 1. The ANSI C rand() and srand() functions.
> > 2. The BSD random() and srandom() functions.
> > 
> > 1 is available on all platforms, but some implementations have poor
> > entropy.
> > 
> > 2 may not be available on all platforms; it is available in BSD4.3
> > onwards, and in GNU libc. If it isn't available, 1 could be used
> > instead. Alternatively, the code could be taken from GNU libc.
> 
> My colleague recommends drand48() - maybe not surprising for you.
> I don't know too much about this stuff.
> 
> Please keep in mind that drand48() is lacking on Cygwin and MacOSX,
> compare for a workaround:
> src/raster/r.mapcalc/mapcalc/xrand.c

OK; I'll use drand48() if it's available. And fix xrand.c.

-- 
Glynn Clements <glynn.clements at virgin.net>



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