FCIRCONV

Purpose:

Performs circular convolution using the FFT method.

FCIRCONV(series1, series2, length)

series1	-	A series or table.
series2	-	A series or table.
length	-	Optional. An integer, the number of points to process. Defaults to the maximum length of the input series.

A series or table.

W1: {1, 2, 3}

W2: {4, 5, 6}

W3: fcirconv(W1, W2)

W3 contains the series {31, 31, 28}, the result of the circular convolution of W1 and W2.

Circular convolution is defined as:

$image\circonv01.gif$

for periodic x[n] with period N such that:

$image\circonv03.gif$

for any integer k.

FCIRCONV performs circular convolution by multiplying the FFTs of the input series. This method is faster than CIRCONV for large series.

See CIRCONV for a direct time domain implementation.