34 lines
845 B
JavaScript
34 lines
845 B
JavaScript
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'use strict';
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var MAX_ITER = 1075; // 1023+52 (subnormals) => BIAS+NUM_SIGNFICAND_BITS-1
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var maxBits = 54; // only 53 bits for fraction
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module.exports = function fractionToBitString(x) {
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var str = '';
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if (x === 0) {
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return str;
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}
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var j = MAX_ITER;
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var y;
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// Each time we multiply by 2 and find a ones digit, add a '1'; otherwise, add a '0'..
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for (var i = 0; i < MAX_ITER; i += 1) {
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y = x * 2;
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if (y >= 1) {
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x = y - 1; // eslint-disable-line no-param-reassign
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str += '1';
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if (j === MAX_ITER) {
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j = i; // first 1
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}
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} else {
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x = y; // eslint-disable-line no-param-reassign
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str += '0';
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}
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// Stop when we have no more decimals to process or in the event we found a fraction which cannot be represented in a finite number of bits...
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if (y === 1 || i - j > maxBits) {
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return str;
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}
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}
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return str;
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};
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