Yes, I did have a look, especially as one approach to the problem I
was examining was
to construct a set of coefficients modulo M based on polynomial
multiplication.
eg
(1 + ax)(1 + bx)(a+cx) .... = 1 + (a+b+c+...)x + (ab + bc + ca + ...)x^2
+ ...
for which we should be able to use
add =: M&|@+
by =: M&|@*
ppr =: add//.@(by/) NB. adapted from the Wiki essay
with
ppr/ 1,. a,b,c,...
but it looked to me as if I'd have to invoke the fft multiplier in
scalar fashion.
I'm happy to be proved wrong.
But I'm probably on the wrong tack for the problem as a whole!
Thanks, Raul
Mike
On 08/05/2017 14:19, Raul Miller wrote:
On Mon, May 8, 2017 at 4:43 AM, 'Mike Day' via Programming
<[email protected]> wrote:
Is there a better way to do modulus multiply with largish arguments?
Hypothetically speaking, you might be able to do something based on
http://code.jsoftware.com/wiki/Essays/FFT
I hope this helps,
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