Examples
x = [1 2 3; 4 5 6; 7 8 9] n = 3 dim = 2 fft1 (x, n, dim) ans = 6.0000 + 0.0000i -1.5000 + 0.8660i -1.5000 - 0.8660i 15.0000 + 0.0000i -1.5000 + 0.8660i -1.5000 - 0.8660i 24.0000 + 0.0000i -1.5000 + 0.8660i -1.5000 - 0.8660i |  |  |
Calculates the discrete Fourier transform of a matrix using Fast Fourier Transform algorithm.
fft (x, n, dim) fft (x, n) fft (x)
input matrix
Specifies the number of elements of x to be used
Specifies the dimention of the matrix along which the FFT is performed
This is an Octave function. The FFT is calculated along the first non-singleton dimension of the array. Thus, FFT is computed for each column of x.
n is an integer specifying the number of elements of x to use. If n is larger than dimention along. which the FFT is calculated, then x is resized and padded with zeros. Similarly, if n is smaller, then x is truncated.
dim is an integer specifying the dimension of the matrix along which the FFT is performed.
x = [1 2 3; 4 5 6; 7 8 9] n = 3 dim = 2 fft1 (x, n, dim) ans = 6.0000 + 0.0000i -1.5000 + 0.8660i -1.5000 - 0.8660i 15.0000 + 0.0000i -1.5000 + 0.8660i -1.5000 - 0.8660i 24.0000 + 0.0000i -1.5000 + 0.8660i -1.5000 - 0.8660i | | |