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The Inverse Discrete Fourier Transform
 Syntax `idft(`z`)` See Also ifft , dft , ifft

Description
Returns a complex matrix containing the inverse discrete Fourier transform of z, where z is an integer, real double-precision or complex matrix. If `N` is the number of rows in z, the (k,j)-th element of the return value is equal to ```          N      1 -----                  __      - >      z   exp[+2 pi \/-1 (i - 1) (k - 1) / N]      N -----   i,j        i = 1 ```for `k` between `1` and `N` and `j` between `1` and the number of columns in z.

Example
If you enter ```      z = {0, 1, 0, 0} ``` only the term with `i = 2` in the summation defining `idft(z)` is nonzero, and the k-th element of `idft(z)` is equal to ```      1             __      - exp[+2 pi \/-1 (k - 1) / 4]      4 ```which is `1/4`, `\sqrt(-1)/4`, `-1/4`, and `-\sqrt(-1)/4`, for `k` equal to `1`, `2`, `3`, and `4`, respectively. If you continue this example by entering ```      idft(z) ``` O-Matrix will respond ```      {      (.25,0)      (0,.25)      (-.25,0)      (0,-.25)      } ```
Mlmode
In Mlmode this function is called `ifft` instead of `idft`. If you continue the example above by entering ```      mlmode      ifft(z) ``` O-Matrix will respond ```      {      (.25,0)      (0,.25)      (-.25,0)      (0,-.25)      } ```