[Libre-soc-dev] complex numbers as matrices

[Luke Kenneth Casson Leighton]

On 6/25/21, Brian Cannard <brian at solidstatepros.com> wrote:
> Yes, and there is also this thing called geometric algebra, which fixes the
> type theory for engineering equations.

appreciated.

some context: i am currently looking at FFT and DCT, to implement
reverse-bitorder Loads and also paired +/- multiply-accumulate.

the idea is to be able to do variable size Discrete Fourier in about
20 instructions.

however for full FFT (complex numbers) you have to do a lot more
multiplies, and i wanted to work out what those are, then see if the
schedule can be done as a regular pattern of nested for-loops.

if they can then those patterns can be done in hardware and we can say
we can do full FFT in under NN instructions as well.

right now, you should see how many assembly instructions are needed
for "optimised" FFT, it's deeply shocking, no way it fits in L1 cache.

l.

p.s welcome btw :)