Javascript如何检查商数是否为整数

Question

例子:

1.15 / 0.01 = 114.99999999999999, is an Integer in my case
9.96 / 0.01 = 996.0000000000001, is an Integer in my case
15.121 / 0.01 = 1512.1, Not an Integer

Number.isInteger() 在以下情况下不准确:1.15/0.01 和 9.96/0.01

Answer 1

我建议为此使用专用库，例如​​ decimal.js .

小数对象有一个有用的方法isInteger() , 可以在除法完成后调用。

您可以设置所需的精度，但我认为默认值应该足够了(20，请参阅 precision)

function isQuotientInteger(dividend, divisor) {
    return new Decimal(dividend).dividedBy(new Decimal(divisor)).isInteger();
}

let testInputs = [ { dividend: 1.15, divisor: 0.01 }, { dividend: 9.96, divisor: 0.01 }, { dividend: 15.121, divisor: 0.01 } , { dividend: 3.14159, divisor: 0.00001 }];

formatRow('Dividend', 'Divisor', 'Quotient is integer')
for(let testInput of testInputs) {
    formatRow(testInput.dividend, testInput.divisor, isQuotientInteger(testInput.dividend, testInput.divisor))
}

function formatRow(...row) {
    console.log(...row.map(f => (f + '').padEnd(10)))
}
   

.as-console-wrapper { max-height: 100% !important; top: 0; }

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