#include <stdio.h>
#include <gsl/gsl_sf_clausen.h>

int
main(void)
{
	int i;
	double p[] = { 0.0, 0.5, 4.2, 13.0 };

	printf("Clausen-Funktion:\n");
	for (i = 0; i < sizeof(p) / sizeof(*p); i++) {
		printf("\tCl2(%f)\t=\t%f\n", p[i],
		       gsl_sf_clausen(p[i]));
	}

	return 0;
}