PowerSpectraImport¶

class acoular.spectra.PowerSpectraImport¶

Bases: PowerSpectra

Provides a dummy class for using pre-calculated cross-spectral matrices.

This class does not calculate the cross-spectral matrix. Instead, the user can inject one or multiple existing CSMs by setting the csm attribute. This can be useful when algorithms shall be evaluated with existing CSM matrices. The frequency or frequencies contained by the CSM must be set via the attr:frequencies attribute. The attr:numchannels attributes is determined on the basis of the CSM shape. In contrast to the PowerSpectra object, the attributes sample_freq, time_data, source, block_size, calib, window, overlap, cached, and num_blocks have no functionality.

csm = Property(desc='cross spectral matrix')¶

The cross spectral matrix, (number of frequencies, numchannels, numchannels) array of complex;

frequencies = Trait(None, (CArray, Float), desc='frequencies included in the cross-spectral matrix')¶

frequencies included in the cross-spectral matrix in ascending order. Compound trait that accepts arguments of type list, array, and float

numchannels = Property(depends_on=['digest'])¶

Number of time data channels

basename = Property(depends_on='digest', desc='basename for cache file')¶

Name of the cache file without extension, readonly.

fftfreq()¶

Return the Discrete Fourier Transform sample frequencies.

Returns:

fndarray

Array containing the frequencies.