16 lines
260 B
JavaScript
16 lines
260 B
JavaScript
export default function(pp, B) {
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var cos_2B = 2 * Math.cos(2 * B);
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var i = pp.length - 1;
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var h1 = pp[i];
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var h2 = 0;
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var h;
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while (--i >= 0) {
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h = -h2 + cos_2B * h1 + pp[i];
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h2 = h1;
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h1 = h;
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}
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return (B + h * Math.sin(2 * B));
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}
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