function toms446_test04 ( ) %*****************************************************************************80 % %% TOMS446_TEST04 tests EDCHEB, which evaluates the derivative of a Chebyshev series. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 21 September 2011 % % Author: % % John Burkardt % nf = 5; npl = 10; nx = 6; fprintf ( 1, '\n' ); fprintf ( 1, 'TOMS446_TEST04\n' ); fprintf ( 1, ' Test EDCHEB, which evaluates the \n' ); fprintf ( 1, ' derivative of a Chebyshev series.\n' ); x = cheby ( nf, npl, @functn ); for j = 1 : nf x2(1:npl) = x(1:npl,j); fprintf ( 1, '\n' ); if ( j == 1 ) fprintf ( 1, ' d/dx Sin(x)\n' ); elseif ( j == 2 ) fprintf ( 1, ' d/dx Cos(x)\n' ); elseif ( j == 3 ) fprintf ( 1, ' d/dx Sin(2x)\n' ); elseif ( j == 4 ) fprintf ( 1, ' d/dx Cos(2x)\n' ); elseif ( j == 5 ) fprintf ( 1, ' d/dx x^5\n' ); end fprintf ( 1, '\n' ); for k = 1 : nx xval = 2.0 * ( k - 1 ) / ( nx - 1 ) - 1.0; fxj = functn_d ( xval ); fval = edcheb ( xval, x2, npl ); fprintf ( 1, ' %10.4f %10.4f %10.4f\n', xval, fxj(j), fval ); end end return end