I'm wondering if the problem might be in the extrapolation table qags uses to approach the singularity? You might try editing initialise_table in qelg.c to initialize rlist2[0] and res3la[0] to 0.0 and recompiling GSL and then running...
Take care, Andrew On Thu, Dec 1, 2011 at 2:33 PM, Rhys Ulerich <rhys.uler...@gmail.com> wrote: > Hi Denes, > >> Unfortunately our 'test' code is 400-500 lines. We may be able to reduce it >> in the coming weeks. Apart from all the bells and whistles, the original >> code allocated a single workspace and then used that in a loop to compute >> billions of integrals (calls to gsl_integration_qags()) with stochastic >> parameters. The results were really strange (and wrong) until we changed the >> code to allocate a workspace for every single integration. > > Any chance your test code is overwriting memory in places where it > shouldn't? If it trampled the gsl_integration_workspace I'd expect > similar behavior which might be resolved by allocating new workspaces > all the time. What does valgrind say? Do you see identical (or > identically strange) results across different compiler versions or > optimization levels? > > 400-500 lines isn't ideal but it'd be usable if you can reproduce the > issue with O(2) iterations instead of billions. > > - Rhys > > _______________________________________________ > Help-gsl mailing list > Help-gsl@gnu.org > https://lists.gnu.org/mailman/listinfo/help-gsl _______________________________________________ Help-gsl mailing list Help-gsl@gnu.org https://lists.gnu.org/mailman/listinfo/help-gsl