At Mon, 28 Jan 2008 12:22:32 +0100, Mauro wrote: > I wrote a program that uses Conjugate PR gradient algorithm to minimize a > multivariable function. > The program works fine, but has a strange behavior when I run it on > Valgrind, a software for detect many memory management and threading bugs. > The result of minimization is exactly the same that I obtain without using > valgrind, but the number of iterations is different! > The input data obviously not change...I thought that the cause is Valgrind > because it modifies the memory usage... > But if I copy initialization params array (passed by the minimization > function that initialize PRGC method) using memcpy instead an > element-by-element cycle, the behavior is the same as when I use Valgrind! > What happens?Can be an unwanted compiler optimization?Or it's a bug, or it's > normal?
Maybe rounding. Try using gsl_ieee_env_setup and GSL_IEEE_MODE=double-precision,mask-all. -- Brian Gough _______________________________________________ Help-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gsl
