| Leo Repp | 58b9f11 | 2021-11-22 11:57:47 +0100 | [diff] [blame^] | 1 | var baseRandom = require('./_baseRandom'), |
| 2 | isIterateeCall = require('./_isIterateeCall'), |
| 3 | toFinite = require('./toFinite'); |
| 4 | |
| 5 | /** Built-in method references without a dependency on `root`. */ |
| 6 | var freeParseFloat = parseFloat; |
| 7 | |
| 8 | /* Built-in method references for those with the same name as other `lodash` methods. */ |
| 9 | var nativeMin = Math.min, |
| 10 | nativeRandom = Math.random; |
| 11 | |
| 12 | /** |
| 13 | * Produces a random number between the inclusive `lower` and `upper` bounds. |
| 14 | * If only one argument is provided a number between `0` and the given number |
| 15 | * is returned. If `floating` is `true`, or either `lower` or `upper` are |
| 16 | * floats, a floating-point number is returned instead of an integer. |
| 17 | * |
| 18 | * **Note:** JavaScript follows the IEEE-754 standard for resolving |
| 19 | * floating-point values which can produce unexpected results. |
| 20 | * |
| 21 | * @static |
| 22 | * @memberOf _ |
| 23 | * @since 0.7.0 |
| 24 | * @category Number |
| 25 | * @param {number} [lower=0] The lower bound. |
| 26 | * @param {number} [upper=1] The upper bound. |
| 27 | * @param {boolean} [floating] Specify returning a floating-point number. |
| 28 | * @returns {number} Returns the random number. |
| 29 | * @example |
| 30 | * |
| 31 | * _.random(0, 5); |
| 32 | * // => an integer between 0 and 5 |
| 33 | * |
| 34 | * _.random(5); |
| 35 | * // => also an integer between 0 and 5 |
| 36 | * |
| 37 | * _.random(5, true); |
| 38 | * // => a floating-point number between 0 and 5 |
| 39 | * |
| 40 | * _.random(1.2, 5.2); |
| 41 | * // => a floating-point number between 1.2 and 5.2 |
| 42 | */ |
| 43 | function random(lower, upper, floating) { |
| 44 | if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) { |
| 45 | upper = floating = undefined; |
| 46 | } |
| 47 | if (floating === undefined) { |
| 48 | if (typeof upper == 'boolean') { |
| 49 | floating = upper; |
| 50 | upper = undefined; |
| 51 | } |
| 52 | else if (typeof lower == 'boolean') { |
| 53 | floating = lower; |
| 54 | lower = undefined; |
| 55 | } |
| 56 | } |
| 57 | if (lower === undefined && upper === undefined) { |
| 58 | lower = 0; |
| 59 | upper = 1; |
| 60 | } |
| 61 | else { |
| 62 | lower = toFinite(lower); |
| 63 | if (upper === undefined) { |
| 64 | upper = lower; |
| 65 | lower = 0; |
| 66 | } else { |
| 67 | upper = toFinite(upper); |
| 68 | } |
| 69 | } |
| 70 | if (lower > upper) { |
| 71 | var temp = lower; |
| 72 | lower = upper; |
| 73 | upper = temp; |
| 74 | } |
| 75 | if (floating || lower % 1 || upper % 1) { |
| 76 | var rand = nativeRandom(); |
| 77 | return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper); |
| 78 | } |
| 79 | return baseRandom(lower, upper); |
| 80 | } |
| 81 | |
| 82 | module.exports = random; |