BaseSpectra¶

class acoular.spectra.BaseSpectra¶

Bases: ABCHasStrictTraits

source = Instance(SamplesGenerator)¶

Data source; SamplesGenerator or derived object.

sample_freq = Delegate('source')¶

Sampling frequency of output signal, as given by source.

num_channels = Delegate('source')¶

Number of time data channels

window = Map( …¶

Window function for FFT, one of: * ‘Rectangular’ (default) * ‘Hanning’ * ‘Hamming’ * ‘Bartlett’ * ‘Blackman’

overlap = Map({'None': 1, '50%': 2, '75%': 4, '87.5%': 8}, default_value='None', desc='overlap of FFT blocks')¶

Overlap factor for averaging: ‘None’(default), ‘50%’, ‘75%’, ‘87.5%’.

block_size = Enum( …¶

FFT block size, one of: 128, 256, 512, 1024, 2048 … 65536, defaults to 1024.

precision = Enum('complex128', 'complex64', desc='precision of the fft')¶

The floating-number-precision of the resulting spectra, corresponding to numpy dtypes. Default is ‘complex128’.

fftfreq()¶

Return the Discrete Fourier Transform sample frequencies.

Returns:

fndarray

Array of length block_size/2+1 containing the sample frequencies.