53 lines
1.4 KiB
JavaScript
53 lines
1.4 KiB
JavaScript
"use strict";
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Object.defineProperty(exports, "__esModule", {
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value: true
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});
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exports.createBellNumbers = void 0;
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var _factory = require("../../utils/factory.js");
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const name = 'bellNumbers';
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const dependencies = ['typed', 'addScalar', 'isNegative', 'isInteger', 'stirlingS2'];
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const createBellNumbers = exports.createBellNumbers = /* #__PURE__ */(0, _factory.factory)(name, dependencies, _ref => {
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let {
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typed,
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addScalar,
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isNegative,
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isInteger,
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stirlingS2
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} = _ref;
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/**
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* The Bell Numbers count the number of partitions of a set. A partition is a pairwise disjoint subset of S whose union is S.
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* bellNumbers only takes integer arguments.
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* The following condition must be enforced: n >= 0
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*
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* Syntax:
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*
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* math.bellNumbers(n)
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*
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* Examples:
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*
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* math.bellNumbers(3) // returns 5
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* math.bellNumbers(8) // returns 4140
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*
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* See also:
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*
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* stirlingS2
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*
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* @param {Number | BigNumber} n Total number of objects in the set
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* @return {Number | BigNumber} B(n)
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*/
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return typed(name, {
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'number | BigNumber': function (n) {
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if (!isInteger(n) || isNegative(n)) {
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throw new TypeError('Non-negative integer value expected in function bellNumbers');
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}
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// Sum (k=0, n) S(n,k).
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let result = 0;
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for (let i = 0; i <= n; i++) {
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result = addScalar(result, stirlingS2(n, i));
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}
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return result;
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}
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});
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}); |