23 lines
623 B
TypeScript
23 lines
623 B
TypeScript
export const pickRandom = <T>(arr: T[]) => {
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const index = Math.floor(Math.random() * arr.length);
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return arr[index];
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};
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export const weightedPickRandom = <T>(
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arr: T[],
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getWeight: (item: T) => number = () => 1,
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getRandom: (tw: number) => number = (totalWeight) =>
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Math.random() * totalWeight,
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): T => {
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const totalWeight = arr.reduce((acc, cur) => acc + getWeight(cur), 0);
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const random = getRandom(totalWeight);
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let currentWeight = 0;
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for (const entry of arr) {
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currentWeight += getWeight(entry);
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if (random < currentWeight) {
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return entry;
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}
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}
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return arr[arr.length - 1];
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};
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