Hi, the problem is the limited precision of 'double' operations, see
http://en.wikipedia.org/wiki/Floating_point#Accuracy_problems The sum or product of two doubles can generally not be represented as a double, and therefore, rounding errors occur. A consequence of this is that the result of a summation can depend on the order in which the terms are added, and that's what happens in your example. The relative difference between the two results you expected to be equal is about 1e-16, and that's in the range of rounding errors you can expect for double operations. Frank _______________________________________________ Help-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gsl
