21 lines
619 B
JavaScript
21 lines
619 B
JavaScript
import { randomInt } from '../math/randomInt.mjs';
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function sampleSize(array, size) {
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if (size > array.length) {
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throw new Error('Size must be less than or equal to the length of array.');
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}
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const result = new Array(size);
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const selected = new Set();
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for (let step = array.length - size, resultIndex = 0; step < array.length; step++, resultIndex++) {
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let index = randomInt(0, step + 1);
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if (selected.has(index)) {
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index = step;
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}
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selected.add(index);
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result[resultIndex] = array[index];
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}
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return result;
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}
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export { sampleSize };
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