Date: Apr 7, 2013 7:37 AM
Author: Bruno Luong
Subject: convolution on sparse matrix?

Where it is specified that the convolution of sparse matrices is not allowed?

>> conv([1 2 3],[4 5])

ans =

4 13 22 15

>> conv(sparse([1 2 3]),[4 5])
Undefined function 'conv2' for input arguments of type 'double' and attributes 'sparse col real'.

Error in conv (line 39)
c = conv2(a(:),b(:),shape);

Strange thing is this works just fine:

>> convmtx(sparse([1 2 3]), 2)

ans =

(1,1) 1
(1,2) 2
(2,2) 1
(1,3) 3
(2,3) 2
(2,4) 3

Similar question might be asked for FFT, ...

Bruno