function lattice_rule_test085 ( ) %*****************************************************************************80 % %% LATTICE_RULE_TEST085 tests LATTICE. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 18 November 2008 % % Author: % % John Burkardt % % Reference: % % Ian Sloan, Stephen Joe, % Lattice Methods for Multiple Integration, % Oxford, 1994, page 18. % dim_num = 2; fprintf ( 1, '\n' ); fprintf ( 1, 'LATTICE_RULE_TEST085\n' ); fprintf ( 1, ' LATTICE is a lattice rule for periodic functions.\n' ); fprintf ( 1, ' However, we apply it to a nonperiodic function\n' ); fprintf ( 1, ' just to see how it does.\n' ); fprintf ( 1, '\n' ); fprintf ( 1, ' The spatial dimension DIM_NUM = %d\n', dim_num ); a(1:dim_num) = 0.0; b(1:dim_num) = 1.0; exact = e_01_2d ( dim_num, a, b ); z(1:dim_num) = [ 1, 2 ]; i4vec_print ( dim_num, z, ' The lattice generator vector:' ); fprintf ( 1, '\n' ); fprintf ( 1, ' K M EXACT ESTIMATE ERROR\n' ); fprintf ( 1, '\n' ); for k = 3 : 18 m = fibonacci ( k ); quad = lattice ( dim_num, m, z, @f_01_2d ); error = abs ( exact - quad ); fprintf ( 1, ' %8d %8d %10.6f %10.6f %10.6e\n', k, m, exact, quad, error ); end return end