/* nag_bessel_k_alpha (s18egc) Example Program. * * Copyright 2000 Numerical Algorithms Group. * * NAG C Library * * Mark 6, 2000. * Mark 8 revised, 2004. */ #include #include #include #include int main(void) { Integer exit_status = 0, i, ia, ja, nl; NagError fail; double alpha, *b = 0, x; INIT_FAIL(fail); /* Skip heading in data file */ scanf("%*[^\n]"); printf("nag_bessel_k_alpha (s18egc) Example Program Results\n"); if (!(b = NAG_ALLOC(101, double))) { printf("Allocation failure\n"); exit_status = -1; goto END; } while (scanf("%lf %ld %ld %ld%*[^\n]", &x, &ia, &ja, &nl) != EOF) { printf(" x ia ja nl\n"); printf("%4.1f %6ld %6ld %6ld\n\n", x, ia, ja, nl); /* nag_bessel_k_alpha (s18egc). * Modified Bessel functions K_(alpha+n)(x) for real * x > 0, selected values of alpha >= 0 and * n = 0,1,...,N */ nag_bessel_k_alpha(x, ia, ja, nl, b, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_bessel_k_alpha (s18egc).\n%s\n", fail.message); exit_status = 1; goto END; } printf(" Requested values of K_alpha(x)\n\n"); alpha = (double) ia / (double) ja; printf(" alpha K_alpha(x)\n"); for (i = 0; i <= nl; ++i) { printf(" %13.4e %13.4e\n", alpha, b[i]); alpha += 1.0; } } END: NAG_FREE(b); return exit_status; }