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function res = fft1 (x, n, dim)
//Calculates the discrete Fourier transform of a matrix using Fast Fourier Transform algorithm.
//Calling Sequence
//fft (x, n, dim)
//fft (x, n)
//fft (x)
//Parameters
//x: input matrix
//n: Specifies the number of elements of x to be used
//dim: Specifies the dimention of the matrix along which the FFT is performed
//Description
//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.
//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
funcprot(0);
lhs = argn(1)
rhs = argn(2)
if (rhs < 1 | rhs > 3)
error("Wrong number of input arguments.")
end
select(rhs)
case 1 then
res = callOctave("fft", x)
case 2 then
res = callOctave("fft", x, n)
case 3 then
res = callOctave("fft", x, n, dim)
end
endfunction
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