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Show HN: Floating point arithmetic types in C++ for any size and any base

(github.com)
79 points seg_fault | 2 comments | 18 Oct 24 17:42 UTC | HN request time: 0.515s | source

Since there is so much interest on HN in floats lately and their software implementations, I wanted to show mine. It has no use and is just for teaching me floats and C++. Give me your thoughts.
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amelius ◴[22 Oct 24 08:25 UTC] No.41912300[source]▶
Isn't this in libgmp already?

https://gmplib.org/

replies(1): >>41912409 #
Archit3ch ◴[22 Oct 24 08:51 UTC] No.41912409[source]▶
GMP doesn't do arbitrary exponents.
replies(1): >>41912498 #
amelius ◴[22 Oct 24 09:06 UTC] No.41912498[source]▶
Indeed, thanks.
replies(1): >>41914101 #
1. Archit3ch ◴[22 Oct 24 13:33 UTC] No.41914101[source]▶
Slight correction, while the exponent is indeed fixed, it is larger than a f32/f64 exponent: https://gmplib.org/manual/Floating_002dpoint-Functions

However, this is not exposed in all GMP wrappers.

replies(1): >>41916884 #
2. seg_fault ◴[22 Oct 24 17:57 UTC] No.41916884[source]▶
If I understand this correctly GMP has a flexible mantissa with no limitations during runtime.

In fas you have to specify the sizes (of mantissa and exponent) during compile time. So the size of this type is fixed. Thus, there is no heap involved.