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16:52:45
Colleen
<|3b|> shinmera: off-topic for #sbcl, but have you seen sb-cga's stuff for avoiding consing of intermediate results?
16:55:33
Colleen
<|3b|> ACTION feels like writing big nested matrix math forms isn't really all that common though, at least for the things i'd expect to take up a lot of time... i'm more likely to worry about things like "here's a big tree of matrices, multiply each by its parent"
17:11:06
Colleen
<shinmera> I'm more worried about consing up a bunch of dumb vectors that go nowhere.
17:19:20
Colleen
<|3b|> actually, i guess it was vector ops that it optimized, and probably even less likely to have big nested forms of
17:21:09
Colleen
<|3b|> https://github.com/nikodemus/sb-cga/blob/master/vec.lisp#L21-L47 and https://github.com/nikodemus/sb-cga/blob/master/vm.lisp#L250-L278
17:22:07
Colleen
<|3b|> i think sb-cga was written along with a (CPU-only) ray tracer, so optimizes for different things than we usually care about
18:28:49
Colleen
<selwyn> i have somewhat of the inverse problem in that i implement matrix algorithms that rely on somewhat intricate block matrix decompositions
18:29:22
Colleen
<selwyn> but if they are not as fast as they could be, it is not the end of the world