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Dhairya Shah
Dhairya Shah

Posted on • Originally published at codewithsnowbit.hashnode.dev

JavaScript is Crazy - Part 2

#javascript #webdev

Hello Folks 👋

What’s up friends, this is SnowBit here. I am a young passionate and self-taught developer and have an intention to become a successful developer.

Today, I am here again with a crazy thing in JavaScript.

So, let’s get started.

console.log(Math.max())
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As we all know the biggest positive number is ∞ (infinity). So the out of the above code snippet should be positive Infinity. For better understanding, you can see the attached graph

graph

console.log(Math.max())
// -Infinity
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But, as we know JavaScript is crazy 🤪; The output of this code is -Infinity. Don't believe it? check out the demo - https://jsfiddle.net/ce0hkoLs/

Now, here come Math.min() it is converse of Math.max

As we all know that lowest negative number is -∞(-infinity), but we know that’s not the case.

console.log(Math.min())
// Infinity
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We all know simple math, right? Now again we have a crazy thing with mathematics in JavaScript.

console.log(0.5 + 0.1 == 0.6)
// true
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Yes, 0.5 + 0.1 == 0.6 is true, isn’t it?

Now here comes some thing crazy,

console.log(0.1 + 0.2 == 0.3)
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As we know, 0.1 + 0.2 == 0.3 is true, but JavaScript don’t think that. Somehow, JavaScript thinks it is false, I actually don’t know the exact reason for that let me know in the comments if you know it.

There, the output will be,

console.log(0.1 + 0.2 == 0.3)
// false
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Try it - https://jsfiddle.net/feahj1s2/

Thank you for reading, have a nice day!
Your appreciation is my motivation 😊

Oldest comments (4)

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dhairyashah profile image
Dhairya Shah •

Great explaination!

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darkwiiplayer profile image
𒎏Wii 🏳️‍⚧️ •

It actually makes a lot of sense that the maximum of nothing is the lowest possible number.

Consider this example:

let a = [/* some numbers */]
let b = [/* some numbers */]
Math.max(Math.max(...a), Math.max(...b))
// Should be the same as
Math.max(...a, ...b)
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Consider now that a = [] and b = [2]

If Math.max(...[]), which is the same as Math.max() returned positive infinity, then the first example would be Math.max(Math.max(), Math.max(2)) which would return positive infinity, even though the second example would return 2 because Math.max(...[], ...[2]) is the same as just Math.max(2).

The second one is really just the age-old topic of floating point inaccuracy. It's interesting to explore why it happens with one set of numbers but not with another, but on its own, it's really just a well-known phenomenon.

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jonrandy profile image
Jon Randy 🎖️ •

As for the second point, it is not really a JavaScript issue - rather it is an issue with the way floating point (decimal) numbers are stored internally. This website gives a fairly succinct explanation and examples of the issue in various languages.

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dhairyashah profile image
Dhairya Shah •

haha, website is amazing specially url