High precision floating point numbers in Haskell?

Question

I know Haskell has native data types which allow you to have really big integers so things like

>> let x = 131242358045284502395482305
>> x
1312         


        

Answer 1

Haskell does not have high-precision floating-point numbers naitively.

For a package/module/library for this purpose, I'd refer to this answer to another post. There's also an example which shows how to use this package, called numbers.

Answer 2

If you need a high precision /fast/ floating point calculations, you may need to use FFI and long doubles, as the native Haskell type is not implemented yet (see https://ghc.haskell.org/trac/ghc/ticket/3353).

Answer 3

Depending on exactly what you are looking for:

• Float and Double - pretty much what you know and "love" from Floats and Doubles in all other languages.
• Rational which is a Ratio of Integers
• FixedPoint - This package provides arbitrary sized fixed point values. For example, if you want a number that is represented by 64 integral bits and 64 fractional bits you can use FixedPoint6464. If you want a number that is 1024 integral bits and 8 fractional bits then use $(mkFixedPoint 1024 8) to generate type FixedPoint1024_8.
• EDIT: And yes, I just learned about the numbers package mentioned above - very cool.