BUILT-IN MATHEMATICA SYMBOL

# Periodogram

Periodogram[list]
plots the squared magnitude of the discrete Fourier transform (power spectrum) of list.

Periodogram[list, n]
plots the mean of power spectra of non-overlapping partitions of length n.

Periodogram[list, n, d]
uses partitions with offset d.

Periodogram[list, n, d, wfun]
applies a smoothing window wfun to each partition.

Periodogram[list, n, d, wfun, m]
pads partitions with zeros to length m prior to the computation of the transform.

Periodogram[{list1, list2, ...}, n, d, wfun, m]
plots power spectra of several lists.

## Details and OptionsDetails and Options

• In Periodogram[list, n, d, wfun], the smoothing window wfun can be specified using a window function that will be sampled between and , or a list of length n. The default window is DirichletWindow, which effectively does no smoothing.
• Periodogram[list, n] is equivalent to Periodogram[list, n, n, DirichletWindow, n].
• For real input data, Periodogram displays only the first half of the power spectrum due to the symmetry property of the Fourier transform.
• Periodogram also works with SampledSoundList objects. When applied to a multichannel sound object, it plots power spectra of all channels.
• Periodogram takes the following options:
•  FourierParameters {0,1} Fourier parameters SampleRate Automatic the sample rate ScalingFunctions "dB" the scaling function
• With the setting SampleRate->r, signal frequencies are shown in the range from to r/2.
• The scaling function can be or , which correspond to the decibel and absolute power values, respectively.
• Periodogram also accepts all options of ListLinePlot.

## ExamplesExamplesopen allclose all

### Basic Examples (2)Basic Examples (2)

Power spectrum of a noisy dataset:

 Out[1]=

Periodogram of a SampledSoundList object:

 Out[1]=