/* nag_1d_quad_gen(d01ajc) Example Program * * Copyright 1991 Numerical Algorithms Group. * * Mark 2, 1991. * Mark 6 revised, 2000. * Mark 7 revised, 2001. */ #include #include #include #include #include #include #ifdef __cplusplus extern "C" { #endif static double f(double x); #ifdef __cplusplus } #endif int main(void) { double a, b; double epsabs, abserr, epsrel, result; Nag_QuadProgress qp; Integer max_num_subint; static NagError fail; double pi = X01AAC; Vprintf("d01ajc Example Program Results\n"); epsabs = 0.0; epsrel = 0.0001; a = 0.0; b = pi*2.0; max_num_subint = 200; d01ajc(f, a, b, epsabs, epsrel, max_num_subint, &result, &abserr, &qp, &fail); Vprintf("a - lower limit of integration = %10.4f\n", a); Vprintf("b - upper limit of integration = %10.4f\n", b); Vprintf("epsabs - absolute accuracy requested = %9.2e\n", epsabs); Vprintf("epsrel - relative accuracy requested = %9.2e\n\n", epsrel); if (fail.code != NE_NOERROR) Vprintf("%s\n", fail.message); if (fail.code != NE_INT_ARG_LT && fail.code != NE_ALLOC_FAIL) { Vprintf("result - approximation to the integral = %9.5f\n", result); Vprintf("abserr - estimate of the absolute error = %9.2e\n", abserr); Vprintf("qp.fun_count - number of function evaluations = %4ld\n", qp.fun_count); Vprintf("qp.num_subint - number of subintervals used = %4ld\n", qp.num_subint); /* Free memory used by qp */ NAG_FREE(qp.sub_int_beg_pts); NAG_FREE(qp.sub_int_end_pts); NAG_FREE(qp.sub_int_result); NAG_FREE(qp.sub_int_error); return EXIT_SUCCESS; } else return EXIT_FAILURE; } static double f(double x) { double pi = X01AAC; return (x*sin(x*30.0)/sqrt(1.0-x*x/(pi*pi*4.0))); }