23 lines
625 B
JavaScript
23 lines
625 B
JavaScript
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import pj_mlfn from "./pj_mlfn";
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import {EPSLN} from '../constants/values';
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var MAX_ITER = 20;
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export default function(arg, es, en) {
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var k = 1 / (1 - es);
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var phi = arg;
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for (var i = MAX_ITER; i; --i) { /* rarely goes over 2 iterations */
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var s = Math.sin(phi);
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var t = 1 - es * s * s;
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//t = this.pj_mlfn(phi, s, Math.cos(phi), en) - arg;
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//phi -= t * (t * Math.sqrt(t)) * k;
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t = (pj_mlfn(phi, s, Math.cos(phi), en) - arg) * (t * Math.sqrt(t)) * k;
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phi -= t;
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if (Math.abs(t) < EPSLN) {
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return phi;
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}
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}
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//..reportError("cass:pj_inv_mlfn: Convergence error");
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return phi;
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}
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