Constant cdshealpix::TRANSITION_LATITUDE

pub const TRANSITION_LATITUDE: f64 = 0.729_727_656_226_966_3_f64;

Limit on the latitude (in radians) between the equatorial region and the polar caps. Equals asin(2/3) = 0.7297276562269663 radians ~= 41,81 degrees. Written $\theta_X$ in Calabretta2007.

use cdshealpix::{TRANSITION_LATITUDE};
assert_eq!(f64::asin(2f64 / 3f64), TRANSITION_LATITUDE);