From 3ce34980d7ba2bddbf3e9a1bd6f98cbc855bddc2 Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Sat, 19 Oct 2024 18:21:54 +0200 Subject: First commit MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- libtellurian_transverse_radius_radians.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) create mode 100644 libtellurian_transverse_radius_radians.c (limited to 'libtellurian_transverse_radius_radians.c') diff --git a/libtellurian_transverse_radius_radians.c b/libtellurian_transverse_radius_radians.c new file mode 100644 index 0000000..dae8f04 --- /dev/null +++ b/libtellurian_transverse_radius_radians.c @@ -0,0 +1,14 @@ +/* See LICENSE file for copyright and license details. */ +#include "common.h" + + +double +libtellurian_transverse_radius_radians(double latitude) +{ + double a = LIBTELLURIAN_EQUATORIAL_RADIUS; + double b = LIBTELLURIAN_POLAR_RADIUS; + double f = 1.0 - b / a; + double neg_e2 = (f - 2.0) * f; + double s = sin(latitude); + return pow(fma(neg_e2, s * s, 1.0), -0.5); +} -- cgit v1.2.3-70-g09d2