At Tue, 7 Oct 2008 09:55:06 -0600 (MDT), L. A. Pritchett-Sheats wrote: > I'm writing an integration package which calculates N dimensional > integrals on infinite intervals using the GSL Monte Carlo functions. I'm > using tan(pi/2 x) to transform the integral to the (0,1) domain. For > different functions, I've seen negative values for the chi/dof values. > This is a reproducer integrating a gaussian on (0,+inf) that follows the > sample code found in the GSL manual where I've seen this problem on both a > Mac ( 10.4.11, Intel ) and a Linux machine (AMD Operton 86x_64). Although > the values differ on the two machines, at least 2-3 calls in the loop will > return a negative value for chi/dof. > > I searched through the bug list archives and I didn't see this reported. > Is this a bug or am I doing something wrong here?
Thanks for the email. I have logged that as a bug -- negative chisq should certainly not be returned, wherever it is coming from. https://savannah.gnu.org/bugs/index.php?24510 -- Brian Gough GNU Scientific Library - http://www.gnu.org/software/gsl/ _______________________________________________ Help-gsl mailing list Help-gsl@gnu.org http://lists.gnu.org/mailman/listinfo/help-gsl
