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| Syntax |
dft(z) |
| See Also | fft , idft , fft , lombft |
N is the number of rows in z,
the (k,j)-th element of the return value is equal to
N
----- __
> z exp[-2 pi \/-1 (i - 1) (k - 1) / N]
----- i,j
i = 1
k between 1 and N
and j between 1 and the number of columns in z.
z = {0, 1, 0, 0}
only the term with i = 2 in the summation defining
dft(z) is nonzero, and the k-th element of
dft(z) is equal to
__
exp[-2 pi \/-1 (k - 1) / 4]
1, -\sqrt(-1), -1, and \sqrt(-1),
for k equal to 1, 2, 3, and 4, respectively.
If you continue this example by entering
dft(z)
O-Matrix will respond
{
(1,0)
(0,-1)
(-1,0)
(0,1)
}
fft
instead of dft.
If you continue the example above by entering
mlmode
fft(z)
O-Matrix will respond
{
(1,0)
(0,-1)
(-1,0)
(0,1)
}