3 ms·
Double-double: 31 digits of precision without leaving the FPU
- tobias2014 2mo agoAI has rediscovered https://www.davidhbailey.com/dhbsoftware/ https://www.davidhbailey.com/dhbsoftware/ and similar? Or are there algorithmic improvements? Without referencing established double-double work it's hard to know.
- aappleby 2mo agoFun fact - Google Maps does something similar to this in WebGL in order to keep accurate coordinates across a planet-sized map using only 32-bit floats.
- iliketrains 2mo agoThis sounds interesting, is this documented somewhere?
- wolfd 2mo agoCould be a neat post, but it was too obviously LLM-generated for me to care about reading it deeply. I’m really fine with people using LLMs to write code and understand stuff, but at least drop a disclaimer when you’re blogging straight Claude text.
- squiffsquiff 2mo agoCould call it... 'a Hamburglar'
- akomtu 2mo agoReads like AI slop. It circles around the point, uses C# examples while talking about FPU, duplicates examples and so on.
- ncruces 2mo agoI have a Go library implementing double-double arithmetic (and also exponentials, logarithms, trigonometry...): https://github.com/ncruces/dbldbl https://github.com/ncruces/dbldbl Mostly useless, but was quite fun to write.
- Scene_Cast2 2mo agoIf you need that precision, especially for position and not values, why use floats at all?
- nickdothutton 2mo agoAt least Dekker is referenced.
- Panzerschrek 2mo agoSuch trick looks interesting. But I think for many cases it would be better to use fixed-width arithmetic based on 128-bit integers. Operations for them are much cheaper if done right (and assuming compilers are smart enough to optimize them). For the Mandelbrot set one don't need huge range, maybe 4 bits of range or so, the remaining 124 bits of precision can increase quality significantly.
- iliketrains 2mo ago[dead]
- suprjami 2mo agoThis feels like a lot of words to say "a decimal point between two integers".