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/* See LICENSE file for copyright and license details. */
#include "common.h"
#ifndef TEST
double
libtellurian_gaussian_radius_radians(double latitude)
{
double a = LIBTELLURIAN_EQUATORIAL_RADIUS;
double b = LIBTELLURIAN_POLAR_RADIUS;
double c = b / a;
double neg_e2 = fma(c, c, -1.0);
double neg_e2_plus_1 = c * c;
double s = sin(latitude);
double denom = fma(neg_e2, s * s, 1.0);
return a * sqrt(neg_e2_plus_1) / denom;
}
#else
static int
check(double lat)
{
double g = libtellurian_gaussian_radius_radians(lat);
double m = libtellurian_meridian_radius_radians(lat);
double n = libtellurian_transverse_radius_radians(lat);
double e = sqrt(m * n);
double err = fabs((g - e) / e);
return err <= 1.0e-8;
}
int
main(void)
{
ASSERT(check(0));
ASSERT(check(D30));
ASSERT(check(D45));
ASSERT(check(D60));
ASSERT(check(D90));
ASSERT(check(D180));
ASSERT(check(-D30));
ASSERT(check(-D45));
ASSERT(check(-D60));
ASSERT(check(-D90));
ASSERT(check(-D180));
ASSERT(check(1.0));
ASSERT(check(2.0));
ASSERT(check(3.0));
return 0;
}
#endif
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