Comparing negative numbers in javascript

Question

I'm sure this is a simple problem, but I'm comparing negative numbers in javascript i.e.:

var num1 = -83.778;
var num2 = -83.356;

if(num1 < num2)
{
    // Take action 1
}
else
{
    // Take action 2
}

This script will always take action 2, even though num1 is less than num2. Whats going on here?

This works for me. >>> -83.778 < -83.356 -> true. Platform / JS Version / Browser version? — g.d.d.c
– g.d.d.c, Commented Aug 9, 2010 at 17:10
Hi, I tested myself, and it take the action 1. There nothing wrong about the comparing here. Maybe your code is wrong somewhere else — Bang Dao
– Bang Dao, Commented Aug 9, 2010 at 17:10
no, it is behaving properly with me.can you please check it again — Jigar Joshi
– Jigar Joshi, Commented Aug 9, 2010 at 17:12
OK, then I must be doing something completely stupid here. Thanks — Tom G
– Tom G, Commented Aug 9, 2010 at 17:19

Seth · Accepted Answer · 2021-03-03 02:28:16Z

25

How does if (parseFloat(num1) < parseFloat(num2)) work? Maybe your numbers are turning into strings somewhere.

edited Mar 3, 2021 at 2:28

answered Aug 9, 2010 at 17:30

Seth

46.8k10 gold badges87 silver badges123 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Tom G Over a year ago

exactly. I was getting the numbers from a JSON response and not parsing them back into floats. Haha sorry everyone....

Vinicius Aquino Over a year ago

Really, JS was comparing two strings with the negative values, thanks for that answer.

Rishabh Sharma · Accepted Answer · 2020-07-10 07:09:14Z

0

This case also works when we want to compare signed characters for both positive and negative numbers. For my case i had numbers like +3, +4, 0, -1 etc..

Directly using if(num1 > num2) would compare these values as string and we would get output of string comparision.

Thus to compare signed numbers., compare them via if (parseFloat(num1) < parseFloat(num2))

answered Jul 10, 2020 at 7:09

Rishabh Sharma

5345 silver badges10 bronze badges

Comments

klein · Accepted Answer · 2022-01-21 08:54:15Z

0

I have the same issue. Workaround for that:

var num1 = -83.778;
var num2 = -83.356;
if((num1 - num2) < 0)
{
    // Take action 1
}
else
{
    // Take action 2
}

Now Ation 1 will be used.

answered Jan 21, 2022 at 8:54

klein

1

Collectives™ on Stack Overflow

Comparing negative numbers in javascript

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related