GGD/node_modules/lodash/random.js

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var baseRandom = require('./_baseRandom'),
isIterateeCall = require('./_isIterateeCall'),
toFinite = require('./toFinite');
/** Built-in method references without a dependency on `root`. */
var freeParseFloat = parseFloat;
/* Built-in method references for those with the same name as other `lodash` methods. */
var nativeMin = Math.min,
nativeRandom = Math.random;
/**
* Produces a random number between the inclusive `lower` and `upper` bounds.
* If only one argument is provided a number between `0` and the given number
* is returned. If `floating` is `true`, or either `lower` or `upper` are
* floats, a floating-point number is returned instead of an integer.
*
* **Note:** JavaScript follows the IEEE-754 standard for resolving
* floating-point values which can produce unexpected results.
*
* @static
* @memberOf _
* @since 0.7.0
* @category Number
* @param {number} [lower=0] The lower bound.
* @param {number} [upper=1] The upper bound.
* @param {boolean} [floating] Specify returning a floating-point number.
* @returns {number} Returns the random number.
* @example
*
* _.random(0, 5);
* // => an integer between 0 and 5
*
* _.random(5);
* // => also an integer between 0 and 5
*
* _.random(5, true);
* // => a floating-point number between 0 and 5
*
* _.random(1.2, 5.2);
* // => a floating-point number between 1.2 and 5.2
*/
function random(lower, upper, floating) {
if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) {
upper = floating = undefined;
}
if (floating === undefined) {
if (typeof upper == 'boolean') {
floating = upper;
upper = undefined;
}
else if (typeof lower == 'boolean') {
floating = lower;
lower = undefined;
}
}
if (lower === undefined && upper === undefined) {
lower = 0;
upper = 1;
}
else {
lower = toFinite(lower);
if (upper === undefined) {
upper = lower;
lower = 0;
} else {
upper = toFinite(upper);
}
}
if (lower > upper) {
var temp = lower;
lower = upper;
upper = temp;
}
if (floating || lower % 1 || upper % 1) {
var rand = nativeRandom();
return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper);
}
return baseRandom(lower, upper);
}
module.exports = random;