On Tue, Jul 22, 2014 at 10:07 PM, Anna Petrášová <kratocha...@gmail.com> wrote:
> > > > On Tue, Jul 22, 2014 at 8:14 PM, Glynn Clements <gl...@gclements.plus.com> > wrote: > >> >> Glynn Clements wrote: >> >> > I'm inclined to add both an option (to specify a seed, replacing the >> > environment variable) and a flag (to seed from the system clock or >> > whatever), and having the PRNG generate a fatal error if neither of >> > those are used. >> >> This is now done. >> >> r61350 adds the lrand48/mrand48/drand48 equivalents to lib/gis. Brief >> testing suggests that the results are identical to those generated by >> GNU libc (which should be identical to any other POSIX implementation). >> >> r61352 changes it to generate a fatal error if used prior to seeding. >> >> r61353 changes r.mapcalc so that seeding is performed via seed= or -s. >> The seed (whether specified by seed= or generated for -s) is added to >> the history (for r.mapcalc; r3.mapcalc's create_history() function is >> a stub; do 3D rasters have history?) >> >> Note that GRASS_RND_SEED is no longer supported. That was a hack from >> the time before r.mapcalc used G_parser(). >> >> As I write this, it has occurred to me that the behaviour of rand() >> may be non-deterministic in the presence of certain forms of >> parallelism, e.g. multiple occurences of rand() in the expression(s) >> in conjunction with pthreads. Ultimately we may need to expand the >> PRNG to support explicit state (as per erand48, nrand48 and jrand48). >> > > I added the support for -s and seed to the r.mapcalc gui in 61354. Testing > is very welcome. > > I wonder if there are any modules in core or addons which need to be > updated. > For example all TGRASS tests are affected. > > Anna > >> >> -- >> Glynn Clements <gl...@gclements.plus.com> >> _______________________________________________ >> grass-dev mailing list >> grass-dev@lists.osgeo.org >> http://lists.osgeo.org/mailman/listinfo/grass-dev >> > >
_______________________________________________ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev