ut2/lib/internals/decimalAdjust.js

一个现代 JavaScript 实用工具库。[点击查看在线文档]。

'use strict';

var isFinite = require('../isFinite.js');
var toInteger = require('../toInteger.js');
var toNumber = require('../toNumber.js');
var toString = require('../toString.js');
var native = require('./native.js');

function decimalAdjust(type, value, precision) {
    if (precision === void 0) { precision = 0; }
    var func = Math[type];
    value = toNumber(value);
    precision = native.mathMin(toInteger(precision), 292);
    if (precision === 0 || !isFinite(value)) {
        return func(value);
    }
    var pair = toString(value).split('e');
    value = func(+(pair[0] + 'e' + (pair[1] ? +pair[1] + precision : precision)));
    pair = toString(value).split('e');
    return +(pair[0] + 'e' + (pair[1] ? +pair[1] - precision : -precision));
}

module.exports = decimalAdjust;