Why is there no 2-byte float and does an implementation already exist?

c++ floating-point 16-bit half-precision-float
Samaursa picture Samaursa · Apr 23, 2011 · Viewed 38.7k times · Source

Assuming I am really pressed for memory and want a smaller range (similar to short vs int). Shader languages already support half for a floating-point type with half the precision (not just convert back and forth for the value to be between -1 and 1, that is, return a float like this: shortComingIn / maxRangeOfShort). Is there an implementation that already exists for a 2-byte float?

I am also interested to know any (historical?) reasons as to why there is no 2-byte float.

Answer

T.J. Crowder picture T.J. Crowder · Apr 23, 2011

Re: Implementations: Someone has apparently written half for C, which would (of course) work in C++: https://storage.googleapis.com/google-code-archive-downloads/v2/code.google.com/cellperformance-snippets/half.c

Re: Why is float four bytes: Probably because below that, their precision is so limited.

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