You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
35 lines
1.2 KiB
35 lines
1.2 KiB
var root = require('./_root'), |
|
toInteger = require('./toInteger'), |
|
toNumber = require('./toNumber'), |
|
toString = require('./toString'); |
|
|
|
/* Built-in method references for those with the same name as other `lodash` methods. */ |
|
var nativeIsFinite = root.isFinite, |
|
nativeMin = Math.min; |
|
|
|
/** |
|
* Creates a function like `_.round`. |
|
* |
|
* @private |
|
* @param {string} methodName The name of the `Math` method to use when rounding. |
|
* @returns {Function} Returns the new round function. |
|
*/ |
|
function createRound(methodName) { |
|
var func = Math[methodName]; |
|
return function(number, precision) { |
|
number = toNumber(number); |
|
precision = precision == null ? 0 : nativeMin(toInteger(precision), 292); |
|
if (precision && nativeIsFinite(number)) { |
|
// Shift with exponential notation to avoid floating-point issues. |
|
// See [MDN](https://mdn.io/round#Examples) for more details. |
|
var pair = (toString(number) + 'e').split('e'), |
|
value = func(pair[0] + 'e' + (+pair[1] + precision)); |
|
|
|
pair = (toString(value) + 'e').split('e'); |
|
return +(pair[0] + 'e' + (+pair[1] - precision)); |
|
} |
|
return func(number); |
|
}; |
|
} |
|
|
|
module.exports = createRound;
|
|
|