What are the polynomial points for F(4,5)???

[victorygogogo]

No description provided.

[andravin]

Because F(4,5) is the same degree as F(6,3), the same 7 interpolation points should work for both algorithms.

Generally for any F(m,r) with m+r-2 = n, you can try the same n interpolation points.

Following the example in the README, try

>>> from sympy import Rational
>>> wincnn.showCookToomFilter((0,1,-1,2,-2,Rational(1,2),-Rational(1,2)), 4, 5)

Hope that helps.

[victorygogogo]

thank you very much

[victorygogogo]

(0,1,-1,Rational(1,2),-Rational(1,2),2,-2 this interp can get the right result ?

[andravin]

Yes, the order you list the points in does not matter .. and otherwise your list is the same as mine.

The usual caveat applies: the more interpolation points your algorithm uses, the greater the numeric error when computed with limited precision arithmetic.

Increasingly, I am only interested in the shortest convolution algorithms, because the latest hardware tends not to have enough memory bandwidth to make the larger algorithms efficient. Also F(2,3) can be accurate even with low precision arithmetic.

[victorygogogo]

so if use low precision data type such as float16 ,f(2,3) can ignore the error ?

[andravin]

Yes, F(2,3) should work well with float16 precision, but as always, actually measure the error compared to a high precision direct convolution for your application!

[Shipley1105]

How to compute F(7,3)?