1

I have this JS code: 

var propertyYield = annualRent / propertyValue * 100.0;

In specific scenario the result is 4.999.

So when I do this

propertyYield.toFixed(2)

I'm getting propertyYield of 5.00.

What I want to achieve is to actually get 4.99 instead of 5.00 as rounding to two decimals.

How can I achieve that?

Brian Tompsett - 汤莱恩
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Laziale
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  • Check this thread which have similar problem statement http://stackoverflow.com/a/4912870/4948688 – Ritesh Kashyap Jul 25 '16 at 07:26
  • Please check the article already discussed. [Click here](http://stackoverflow.com/questions/38526389/javascript-always-returns-float-numbers/38526459#38526459) – Lovepreet Singh Jul 25 '16 at 07:34

2 Answers2

5

You could use Math.floor and some additional arithmetics:

Math.floor(15.7784514000 * 100) / 100

Or convert the number into a string, match the number up to the second decimal place and turn it back into a number:

Number(15.7784514000.toString().match(/^\d+(?:\.\d{0,2})?/))

Then you can still call toFixed to get a string with a fixed number of decimal places.

var num1 = Math.floor(15.7784514000 * 100) / 100;
console.log(num1);

var num2 = Number(15.7784514000.toString().match(/^\d+(?:\.\d{0,2})?/));
console.log(num2)
console.log(num2.toFixed(2))
nicael
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Fadhly Permata
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3

Update: As noted by @kuka this does not work for certain decimal numbers due to floating point error math. Don't use this solution - However I'm leaving it here for documentation sake.

Not sure if I know a library method off hand to do that but quick simple old school solution would be this:

Math.floor(4.999 * 100) / 100.0
k2snowman69
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