# include # include # include # include "tetrahedron_integrals.h" int main ( ); void test01 ( ); /******************************************************************************/ int main ( ) /******************************************************************************/ /* Purpose: MAIN is the main program for TETRAHEDRON_INTEGRALS_TEST. Discussion: TETRAHEDRON_INTEGRALS_TEST tests the TETRAHEDRON_INTEGRALS library. Licensing: This code is distributed under the GNU LGPL license. Modified: 15 January 2014 Author: John Burkardt */ { timestamp ( ); printf ( "\n" ); printf ( "TETRAHEDRON_INTEGRALS_TEST\n" ); printf ( " C version\n" ); printf ( " Test the TETRAHEDRON_INTEGRALS library.\n" ); /* Try each sampler on the unit tetrahedron, integrating quadratics. */ test01 ( ); /* Terminate. */ printf ( "\n" ); printf ( "TETRAHEDRON_INTEGRALS_TEST\n" ); printf ( " Normal end of execution.\n" ); printf ( "\n" ); timestamp ( ); return 0; } /******************************************************************************/ void test01 ( ) /******************************************************************************/ /* Purpose: TEST01 uses TETRAHEDRON_SAMPLE_01 to compare exact and estimated integrals. Licensing: This code is distributed under the GNU LGPL license. Modified: 15 January 2014 Author: John Burkardt */ { int e[3]; double error; double exact; int i; int j; int k; int m = 3; int n = 4192; double result; int seed; int test; int test_num = 20; double *value; double *x; printf ( "\n" ); printf ( "TEST01\n" ); printf ( " Estimate monomial integrals using Monte Carlo\n" ); printf ( " over the interior of the unit tetrahedron in 3D.\n" ); /* Get sample points. */ seed = 123456789; x = tetrahedron01_sample ( n, &seed ); printf ( "\n" ); printf ( " Number of sample points used is %d\n", n ); /* Run through the exponents. */ printf ( "\n" ); printf ( " Ex Ey Ez MC-Estimate Exact Error\n" ); printf ( "\n" ); for ( i = 0; i <= 3; i++ ) { e[0] = i; for ( j = 0; j <= 3; j++ ) { e[1] = j; for ( k = 0; k <= 3; k++ ) { e[2] = k; value = monomial_value ( m, n, e, x ); result = tetrahedron01_volume ( ) * r8vec_sum ( n, value ) / ( double ) ( n ); exact = tetrahedron01_monomial_integral ( e ); error = fabs ( result - exact ); printf ( " %2d %2d %2d %14.6g %14.6g %10.2e\n", e[0], e[1], e[2], result, exact, error ); free ( value ); } } } free ( x ); return; }