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Column-wise Convolution Of Matrices Using FFT
Syntax conv(gh)
See Also mlmode_conv , corr , polmul , filter

Description
Returns a matrix that is the column-wise convolution of g with h, where g and h are integer, real, double-precision, or complex matrices with the same column dimension. If ng and nh are the number of rows in the matrices g and h, respectively, the (k,j)-th element of the return value is
      ng
     -----                                   / 0        if k-i+1 < 1
     >      g    H         where  H       = <  0        if k-i+1 > nh
     -----   i,j  k-i+1,j          k-i+1,j   \ h        otherwise
     i = 1                                      k-i+1,j
The return value is a matrix with row dimension equal to ng + nh - 1 with the same type and column dimension as g. An FFT is used to compute the convolution. The polmul function computes a similar value directly.

Example
     g = {1., 1., 1., 1., 1.}
     conv(g, g)'
returns
     [ 1 , 2 , 3 , 4 , 5 , 4 , 3 , 2 , 1 ]