82 lines
2.3 KiB
JavaScript
82 lines
2.3 KiB
JavaScript
var baseRandom = require('./_baseRandom'),
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isIterateeCall = require('./_isIterateeCall'),
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toNumber = require('./toNumber');
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/** Built-in method references without a dependency on `root`. */
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var freeParseFloat = parseFloat;
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/* Built-in method references for those with the same name as other `lodash` methods. */
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var nativeMin = Math.min,
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nativeRandom = Math.random;
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/**
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* Produces a random number between the inclusive `lower` and `upper` bounds.
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* If only one argument is provided a number between `0` and the given number
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* is returned. If `floating` is `true`, or either `lower` or `upper` are floats,
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* a floating-point number is returned instead of an integer.
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*
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* **Note:** JavaScript follows the IEEE-754 standard for resolving
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* floating-point values which can produce unexpected results.
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*
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* @static
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* @memberOf _
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* @category Number
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* @param {number} [lower=0] The lower bound.
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* @param {number} [upper=1] The upper bound.
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* @param {boolean} [floating] Specify returning a floating-point number.
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* @returns {number} Returns the random number.
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* @example
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*
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* _.random(0, 5);
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* // => an integer between 0 and 5
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*
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* _.random(5);
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* // => also an integer between 0 and 5
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*
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* _.random(5, true);
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* // => a floating-point number between 0 and 5
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*
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* _.random(1.2, 5.2);
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* // => a floating-point number between 1.2 and 5.2
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*/
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function random(lower, upper, floating) {
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if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) {
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upper = floating = undefined;
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}
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if (floating === undefined) {
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if (typeof upper == 'boolean') {
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floating = upper;
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upper = undefined;
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}
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else if (typeof lower == 'boolean') {
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floating = lower;
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lower = undefined;
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}
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}
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if (lower === undefined && upper === undefined) {
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lower = 0;
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upper = 1;
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}
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else {
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lower = toNumber(lower) || 0;
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if (upper === undefined) {
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upper = lower;
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lower = 0;
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} else {
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upper = toNumber(upper) || 0;
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}
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}
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if (lower > upper) {
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var temp = lower;
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lower = upper;
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upper = temp;
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}
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if (floating || lower % 1 || upper % 1) {
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var rand = nativeRandom();
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return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper);
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}
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return baseRandom(lower, upper);
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}
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module.exports = random;
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