path: root/libtellurian_azimuthal_radius_radians.c

/* See LICENSE file for copyright and license details. */
#include "common.h"


double
libtellurian_azimuthal_radius_radians(double latitude, double azimuth)
{
	double m = libtellurian_meridan_radius_radians(latitude);
	double n = libtellurian_transverse_radius_radians(latitude);
	double c2 = cos(azimuth) * cos(azimuth);
	double s2 = sin(azimuth) * sin(azimuth);
	double x = c2 / m;
	double y = s2 / n;
	return 1.0 / (x + y);
}