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import {geoProjection as projection} from "d3-geo";
import {asin, pi, sin, sqrt, sqrtPi} from "./math.js";
export function collignonRaw(lambda, phi) {
var alpha = sqrt(1 - sin(phi));
return [(2 / sqrtPi) * lambda * alpha, sqrtPi * (1 - alpha)];
}
collignonRaw.invert = function(x, y) {
var lambda = (lambda = y / sqrtPi - 1) * lambda;
return [lambda > 0 ? x * sqrt(pi / lambda) / 2 : 0, asin(1 - lambda)];
};
export default function() {
return projection(collignonRaw)
.scale(95.6464)
.center([0, 30]);
}