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Re:4-bit floating point FP4 by sc0ttyd on Saturday April 18, 2026 @06:08PM (#47819936)
9 years ago, I shared this as an April Fools joke here on HN.

It seems that life is imitating art.

https://github.com/sdd/ieee754-rrp

Re:4-bit floating point FP4 by Dylan16807 on Saturday April 18, 2026 @07:41PM (#47820498)
> 9 years ago, I shared this as an April Fools joke here on HN.

That's fun.

> It seems that life is imitating art.

You didn't even beat wikipedia to the punch. They've had a nice page about minifloats using 6-8 bit sizes as examples for about 20 years.

The 4 bit section is newer, but it actually follows IEEE rules. Your joke formats forgot there's an implied 1 bit in the fraction. And how exponents work.

Re:4-bit floating point FP4 by mysterydip on Saturday April 18, 2026 @06:13PM (#47819975)
I especially like your HQQ precision
Re:4-bit floating point FP4 by sc0ttyd on Saturday April 18, 2026 @06:44PM (#47820182)
I think it is only a matter of time before HQQ / 1FP takes over. It's the logical conclusion. I hope to be using my 96-blade razor by then too
Re:4-bit floating point FP4 by phendrenad2 on Sunday April 19, 2026 @07:04PM (#47828503)
Re:4-bit floating point FP4 by nomel on Sunday April 19, 2026 @12:07AM (#47821716)
Lowest I've used is 8 bit floats for time delays, in embedded devices.
Re:4-bit floating point FP4 by the__alchemist on Sunday April 19, 2026 @08:25AM (#47823791)
Interesting! I have been using integers or f32 for that. What was the use case specifically? Did you write a software float for it? I remember writing a `f16` type for an IC that used that was a pain!
Re:4-bit floating point FP4 by nomel on Monday April 20, 2026 @09:46AM (#47834267)
Tight memory constraint. I was putting configuration somewhere it shouldn't have been, but it meant we didn't need to buy an extra chip.

Yes, purely software.

Re:4-bit floating point FP4 by lifthrasiir on Sunday April 19, 2026 @12:10AM (#47821731)
Another attempt includes Tom 7's binary3 format [1].

[1] https://tom7.org/nand/