javascript - 将 0.02 添加到 javascript 中的数字会导致不正确的值

Question

我试图通过小数间隔获取从 min 到 max 的数字数组，在本例中为 0.02，例如:1.00 , 1.02, 1.04, 1.06

下面的代码在 1.14 处开始中断:

function getOptions(min, max, interval) {
  var options = [];

  for (var i = min; i <= max; i += interval) {
    options.push(i);
  }

  return options;
}

var options = getOptions(1.0, 1.4, 0.02);

此时，options 就像:

[
    1, 
    1.02, 
    ...
    1.12, 
    1.1400000000000001, 
    1.1600000000000001
    ...
]

是什么原因造成的，我该如何解决？

Answer 1

根据 What Every Programmer Should Know About Floating-Point Arithmetic :

internally, computers use a format (binary floating-point) that cannot accurately represent a number like 0.1, 0.2 or 0.3 at all.

When the code is compiled or interpreted, your “0.1” is already rounded to the nearest number in that format, which results in a small rounding error even before the calculation happens.

对于 Javascript specifically :

JavaScript numbers are really just floating points as specified by IEEE-754. Due to inadequecies when representing numbers in base-2, as well as a finite machine, we are left with a format that is filled with rounding errors. This article explains those rounding errors and why errors occur. Always use a good library for numbers instead of building your own

我在这方面取得了一些成功 BigDecimal port越小，越快big.js .