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18 lines
484 B
JavaScript
18 lines
484 B
JavaScript
import { HALF_PI } from '../constants/values';
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export default function (eccent, ts) {
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var eccnth = 0.5 * eccent;
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var con, dphi;
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var phi = HALF_PI - 2 * Math.atan(ts);
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for (var i = 0; i <= 15; i++) {
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con = eccent * Math.sin(phi);
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dphi = HALF_PI - 2 * Math.atan(ts * (Math.pow(((1 - con) / (1 + con)), eccnth))) - phi;
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phi += dphi;
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if (Math.abs(dphi) <= 0.0000000001) {
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return phi;
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}
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}
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// console.log("phi2z has NoConvergence");
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return -9999;
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}
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