Can I use Infinity and -Infinity as an initial value for Max and Min variables?

Question

I thought that it would be acceptable to initialize my Max value to -Infinity but this did not turn out to be the case in JavaScript.

If Infinity is considered a number type why can't I use it in my comparisons?

  var windowStart =0, sum =0, max = -Infinity
  for(windowEnd=0;windowEnd<k-1;windowEnd++)
  {
    sum += arr[windowStart]
    if(windowEnd>k-1)
    {
      if(sum > max)
        max = sum
      sum -= arr[windowStart]
      windowStart += 1
    }
  }

  return max;

Thanks to the community I noticed that I jumped the gun in posting my question and did not do an appropriate amount of my own debugging. Thank you all for your quick answers.

You can use `Infinity` in comparisons. Please show the code where you're using `Infinity`. — Teemu, Aug 03 '20 at 19:54
`max = -Infinity` is perfectly legal, as is `-Infinity < 4`, for example. What exact problem are you getting? — VLAZ, Aug 03 '20 at 19:54
@freddyhaug Please paste the code into your question instead of posting a screenshot of it. — Dennis Hackethal, Aug 03 '20 at 19:57
Okay, thank you for confirming this, it must just be some separate error in code. I'll poke around thank you thank you sorry sorry — Frederick Haug, Aug 03 '20 at 19:57
This condition `if(windowEnd>k-1)` never passes, as the loop breaks when `windowEnd == k-1`. — Teemu, Aug 03 '20 at 19:59
ooooooo I see I made the for loop stop at k-1 and not arr.length. Thank you Teemu — Frederick Haug, Aug 03 '20 at 20:01

Dennis Hackethal · Accepted Answer · 2020-08-03T19:56:41.297

1

You can use Infinity as you intended:

Math.min(Infinity, 10)
// => 10

Infinity < 10
// => false

edited Aug 03 '20 at 19:56

answered Aug 03 '20 at 19:55

Dennis Hackethal

13,662
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score 0 · Answer 2 · answered Aug 03 '20 at 19:58

0

It looks like it's indeed already being used as default min and max values even in native Math.min and Math.max function implementations

Math.min(); // Infinity
Math.max(); // -Infinity

answered Aug 03 '20 at 19:58

Adassko

5,201
20
37

Can I use Infinity and -Infinity as an initial value for Max and Min variables?

2 Answers2