At Sun, 18 Nov 2007 14:15:26 +0100, Jakub Narebski wrote: > I want to find all zeros of Hermite polynomial up to fairly large order > (up to H_100). I use poly/gsl_poly_orth.c by Richard J. Mathar (found by > Google IIRC), which is not present in GSL 1.10, to calculate Hermite > polynomial using divided differences method. > > Function gsl_poly_complex_solve requires polynomial in generic form; > would this cause problems wrt. numerical accuracy?
For orthogonal polynomials there are specialised methods for finding the roots, e.g. as used for finding the abscissae in Gauss-Hermite integration -- which are the roots of Hermite polynomials. These will work much better than a general polynomial solver as they use the recurrence relations directly to do Newton-Raphson steps. > Is there a GSL method to multiply two polynomials in normal form, > or in divided differences representation? No, but I would accept some functions for this. > Is perhaps Jenkins-Traub ethod of finding all zeros of polynomial (RPOLY) > considered for inclusion in GSL? Is poly/gsl_poly_orth.c? These require some more feedback and testing from users to get incorporated. -- Brian Gough Network Theory Ltd, Publishing Free Software Manuals --- http://www.network-theory.co.uk/ _______________________________________________ Help-gsl mailing list Help-gsl@gnu.org http://lists.gnu.org/mailman/listinfo/help-gsl