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Autocorrelation of *N*-D array

**Library:**DSP System Toolbox / Statistics

The Autocorrelation block computes the autocorrelation
along the first dimension of an *N*-D input array.
The computation can be done in the time domain or frequency domain.
You can specify the domain through the **Computation domain** parameter.
In the time domain, the input signal is convolved with its time-reversed
complex conjugate. In the frequency domain, the block computes the
autocorrelation by taking the Fourier transform of the input signal,
multiplying the Fourier transform with its conjugate, and computing
the inverse Fourier transform of the product. In this domain, depending
on the input length, the block can require fewer computations. For
information on these two computation methods, see Algorithms.

You can specify the maximum lag for autocorrelation using the **Compute
all non-negative lags** and **Maximum non-negative
lag (less than input length)** parameters.

The block accepts fixed-point signals when you set the **Computation
domain** to `Time`

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