NAME

       Math::GSL::Chebyshev - Univariate Chebyshev Series Approximation

SYNOPSIS

           use Math::GSL::Chebyshev qw/:all/;

           my $cheb             = gsl_cheb_alloc(40);
           my $function         = sub { sin(cos($_[0])) };

           gsl_cheb_init($cheb, $function, 0, 10);

           my $x                = gsl_cheb_eval($cheb, 5.5 );
           my ($status,$y,$err) = gsl_cheb_eval_err($cheb, 7.5 );
           gsl_cheb_free($cheb);

DESCRIPTION

       •   "gsl_cheb_alloc($size)"

               my $cheb = gsl_cheb_alloc(50);

           Allocates a new Chebyshev object with $size sample points.

       •   "gsl_cheb_free($cheb)"

           Deallocates memory associated to $cheb. Returns void.

       •   "gsl_cheb_init($cheb,$function, $lower, $upper)"

               gsl_cheb_init($cheb, sub { sin(cos($_[0])) }, 0, 10 );

           Initiate a Chebyshev object with a function and upper and lower bounds.  Returns void.

       •   "gsl_cheb_eval($function, $value)"

               my $evaluated = gsl_cheb_eval($cheb, 5 );

           Returns a Perl scalar of the Chebyshev object $cheb evaluated at $value.

       •   "gsl_cheb_eval_err($cheb, $value)"

               my ($status,$evaluated,$err) = gsl_cheb_eval($cheb, 5 );

           Returns a list consisting of a GSL status code, the evaluate value and the estimated
           error of the evaluation.

       •   "gsl_cheb_eval_n "

       •   "gsl_cheb_eval_n_err "

       •   "gsl_cheb_eval_mode "

       •   "gsl_cheb_eval_mode_e "

       •   "gsl_cheb_calc_deriv($deriv,$cheb) "

              my $status = gsl_cheb_calc_deriv( $deriv, $cheb );

           This will calculate the derivative of $cheb and stores it in $deriv, which must be
           pre-allocated. Returns a GSL status code.

       •   "gsl_cheb_calc_integ($integ,$cheb) "

              my $status = gsl_cheb_calc_integ( $deriv, $cheb );

           This will calculate the derivative of $cheb and stores it in $deriv, which must be
           pre-allocated. Returns a GSL status code.

       For more information on the functions, we refer you to the GSL official documentation:
       <http://www.gnu.org/software/gsl/manual/html_node/>

AUTHORS

       Jonathan "Duke" Leto <jonathan@leto.net> and Thierry Moisan <thierry.moisan@gmail.com>

COPYRIGHT AND LICENSE

       Copyright (C) 2008-2021 Jonathan "Duke" Leto and Thierry Moisan

       This program is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself.