At Wed, 12 Jul 2006 19:23:48 -0500, Duane Nykamp wrote: > The function gsl_linalg_solve_symm_tridiag is documented (and named) as > a solver for a general symmetric tridiagonal system. It uses a variant > of Cholesky decomposition, treating the diagonal differently so that the > algorithm applies to more than just positive definite matrices. > > However, if that diagonal in this decomposition is ever zero (e.g., the > upper-left entry of the original matrix is zero), the algorithm will > divide by zero without checking, producing NaNs.
Thanks for the bug report. I have logged it in the BUGS file. For now I have added a note to the documentation that the routine can fail if the matrix is not positive definite. -- best regards, Brian Gough Network Theory Ltd, Publishing the GSL Manual - http://www.network-theory.co.uk/gsl/manual/ _______________________________________________ Bug-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/bug-gsl
