17 lines
583 B
JavaScript
17 lines
583 B
JavaScript
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// `Math.scale` method implementation
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// https://rwaldron.github.io/proposal-math-extensions/
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module.exports = Math.scale || function scale(x, inLow, inHigh, outLow, outHigh) {
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if (
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arguments.length === 0
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/* eslint-disable no-self-compare -- NaN check */
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|| x != x
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|| inLow != inLow
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|| inHigh != inHigh
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|| outLow != outLow
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|| outHigh != outHigh
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/* eslint-enable no-self-compare -- NaN check */
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) return NaN;
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if (x === Infinity || x === -Infinity) return x;
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return (x - inLow) * (outHigh - outLow) / (inHigh - inLow) + outLow;
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};
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