jiangchengfeiyi-xiaochengxu/node_modules/mathjs/lib/cjs/function/probability/multinomial.js
2025-01-02 11:13:50 +08:00

56 lines
1.6 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.createMultinomial = void 0;
var _collection = require("../../utils/collection.js");
var _factory = require("../../utils/factory.js");
const name = 'multinomial';
const dependencies = ['typed', 'add', 'divide', 'multiply', 'factorial', 'isInteger', 'isPositive'];
const createMultinomial = exports.createMultinomial = /* #__PURE__ */(0, _factory.factory)(name, dependencies, _ref => {
let {
typed,
add,
divide,
multiply,
factorial,
isInteger,
isPositive
} = _ref;
/**
* Multinomial Coefficients compute the number of ways of picking a1, a2, ..., ai unordered outcomes from `n` possibilities.
*
* multinomial takes one array of integers as an argument.
* The following condition must be enforced: every ai <= 0
*
* Syntax:
*
* math.multinomial(a) // a is an array type
*
* Examples:
*
* math.multinomial([1,2,1]) // returns 12
*
* See also:
*
* combinations, factorial
*
* @param {number[] | BigNumber[]} a Integer numbers of objects in the subset
* @return {Number | BigNumber} Multinomial coefficient.
*/
return typed(name, {
'Array | Matrix': function (a) {
let sum = 0;
let denom = 1;
(0, _collection.deepForEach)(a, function (ai) {
if (!isInteger(ai) || !isPositive(ai)) {
throw new TypeError('Positive integer value expected in function multinomial');
}
sum = add(sum, ai);
denom = multiply(denom, factorial(ai));
});
return divide(factorial(sum), denom);
}
});
});