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path: root/src/projection/cylindricalEqualArea.js
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import {asin, cos, sin} from "../math.js";

export function cylindricalEqualAreaRaw(phi0) {
  var cosPhi0 = cos(phi0);

  function forward(lambda, phi) {
    return [lambda * cosPhi0, sin(phi) / cosPhi0];
  }

  forward.invert = function(x, y) {
    return [x / cosPhi0, asin(y * cosPhi0)];
  };

  return forward;
}