How do you handle numbers larger than the max?

When using numbers on Roblox, there is a max number, which I believe is 2,147,483,647 (corrected by CloneTrooper1019). However, some people get around this, such as Mining Simulator:

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What methods can you use to do this?


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You’ll need some implementation of BigNum.

I haven’t tried this module, but it’s in pure Lua 5.1 so it should port over to Roblox nicely with relative ease: euler/BigNum.lua at master · ennorehling/euler · GitHub

Not exactly sure how you’d serialize it to data storage with this module, but that’s something you should be able to look into.

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Can confirm this is working.

Haven’t taken too much of a look at it so I don’t know how i would save the BigNums to a data store yet. Will try figuring that out soon.

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You could also just use number values instead of intvalues

Number values go upto 10^300 and lua can handle them without any outside library

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As far as I know, this isn’t true and I just tested it.

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In fact, it doesn’t seem to work at around 10^23.

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those are called floating point precision errors and occurr because they dont store the full number (kinda)

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I know, thus it’s not useful for the OP’s use cases.

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I managed to JSONEncode and JSONDecode a BigNum. Thanks @Kampfkarren.

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didn’t they increase int values to 64-bit?

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For reference the largest value you can have now is 9,223,372,036,854,775,807 when using an IntValue.

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Also, the maximum integer value that can be stored with precision in a Lua number (or more generally in a double-precision number) is 2^53 or around 15 quadrillion. Depending on your purposes this might not be enough, but it’s good to know.

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And if datastore of the number is an issue, you could potentially save the number as a string and convert it back to a number on loading if it were to be that big of a problem.

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Can you upload the file for the roblox version of BigNum? My ported version is having an error while loading :\

Edit*: Nvm I found this: https://raw.githubusercontent.com/RoStrap/Math/master/BigNum.lua HOWEVER for some reason having a large number powered by itself makes a negative large number rather than a positive cus their both positive.

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I would imagine you could create a separate value for each next big number, for example Value: 10 (Billion), Value: 500 (Million), Value: 875,000 So basically just breaking it up. When it comes to the math, just account for this and add/subtract based on all these values.