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# ifft() - Signal Processing

`y = ifft(X) returns the inverse discrete Fourier transform (DFT) of vector X, computed with a fast Fourier transform (FFT) algorithm.If X is a matrix, ifft returns the inverse DFT of each column of the matrix.ifft tests X to see whether vectors in X along the active dimension are conjugate symmetric.If so, the computation is faster and the output is real.An N-element vector x is conjugate symmetric if x(i) = conj(x(mod(N-i+1,N)+1)) for each element of x.If X is a multidimensional array, ifft operates on the first non-singleton dimension.y = ifft(X,n) returns the n-point inverse DFT of vector X.y = ifft(X,[],dim) and y = ifft(X,n,dim) return the inverse DFT of X across the dimension dim.y = ifft(..., 'symmetric') causes ifft to treat X as conjugate symmetric along the active dimension.This option is useful when X is not exactly conjugate symmetric, merely because of round-off error.y = ifft(..., 'nonsymmetric') is the same as calling ifft(...) without the argument 'nonsymmetric'.For any X, ifft(fft(X)) equals X to within roundoff error.`

### Syntax

```y = ifft(X)
y = ifft(X,n)
y = ifft(X,[],dim)
y = ifft(X,n,dim)
y = ifft(..., 'symmetric')
y = ifft(..., 'nonsymmetric')```

### Example

`You can give an example if you know one.`