152 lines
4.0 KiB
JavaScript
152 lines
4.0 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.createIsPrime = void 0;
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var _collection = require("../../utils/collection.js");
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var _factory = require("../../utils/factory.js");
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var name = 'isPrime';
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var dependencies = ['typed'];
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var createIsPrime = /* #__PURE__ */(0, _factory.factory)(name, dependencies, function (_ref) {
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var typed = _ref.typed;
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/**
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* Test whether a value is prime: has no divisors other than itself and one.
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* The function supports type `number`, `bignumber`.
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*
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* The function is evaluated element-wise in case of Array or Matrix input.
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*
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* Syntax:
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*
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* math.isPrime(x)
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*
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* Examples:
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*
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* math.isPrime(3) // returns true
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* math.isPrime(-2) // returns false
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* math.isPrime(0) // returns false
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* math.isPrime(-0) // returns false
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* math.isPrime(0.5) // returns false
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* math.isPrime('2') // returns true
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* math.isPrime([2, 17, 100]) // returns [true, true, false]
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*
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* See also:
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*
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* isNumeric, isZero, isNegative, isInteger
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*
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* @param {number | BigNumber | Array | Matrix} x Value to be tested
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* @return {boolean} Returns true when `x` is larger than zero.
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* Throws an error in case of an unknown data type.
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*/
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return typed(name, {
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number: function number(x) {
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if (x * 0 !== 0) {
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return false;
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}
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if (x <= 3) {
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return x > 1;
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}
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if (x % 2 === 0 || x % 3 === 0) {
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return false;
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}
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for (var i = 5; i * i <= x; i += 6) {
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if (x % i === 0 || x % (i + 2) === 0) {
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return false;
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}
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}
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return true;
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},
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BigNumber: function BigNumber(n) {
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if (n.toNumber() * 0 !== 0) {
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return false;
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}
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if (n.lte(3)) return n.gt(1);
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if (n.mod(2).eq(0) || n.mod(3).eq(0)) return false;
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if (n.lt(Math.pow(2, 32))) {
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var x = n.toNumber();
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for (var i = 5; i * i <= x; i += 6) {
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if (x % i === 0 || x % (i + 2) === 0) {
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return false;
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}
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}
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return true;
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}
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function modPow(base, exponent, modulus) {
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// exponent can be huge, use non-recursive variant
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var accumulator = 1;
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while (!exponent.eq(0)) {
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if (exponent.mod(2).eq(0)) {
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exponent = exponent.div(2);
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base = base.mul(base).mod(modulus);
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} else {
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exponent = exponent.sub(1);
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accumulator = base.mul(accumulator).mod(modulus);
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}
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}
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return accumulator;
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} // https://en.wikipedia.org/wiki/Miller%E2%80%93Rabin_primality_test#Deterministic_variants
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var Decimal = n.constructor.clone({
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precision: n.toFixed(0).length * 2
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});
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n = new Decimal(n);
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var r = 0;
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var d = n.sub(1);
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while (d.mod(2).eq(0)) {
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d = d.div(2);
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r += 1;
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}
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var bases = null; // https://en.wikipedia.org/wiki/Miller–Rabin_primality_test#Testing_against_small_sets_of_bases
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if (n.lt('3317044064679887385961981')) {
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bases = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41].filter(function (x) {
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return x < n;
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});
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} else {
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var max = Math.min(n.toNumber() - 2, Math.floor(2 * Math.pow(n.toFixed(0).length * Math.log(10), 2)));
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bases = [];
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for (var _i = 2; _i <= max; _i += 1) {
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bases.push(max);
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}
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}
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for (var _i2 = 0; _i2 < bases.length; _i2 += 1) {
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var a = bases[_i2];
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var adn = modPow(n.sub(n).add(a), d, n);
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if (!adn.eq(1)) {
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for (var _i3 = 0, _x = adn; !_x.eq(n.sub(1)); _i3 += 1, _x = _x.mul(_x).mod(n)) {
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if (_i3 === r - 1) {
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return false;
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}
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}
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}
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}
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return true;
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},
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'Array | Matrix': function ArrayMatrix(x) {
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return (0, _collection.deepMap)(x, this);
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}
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});
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});
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exports.createIsPrime = createIsPrime; |