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tempspecf
Temporal power spectrum of vector / scalar fields

Description ```tempspecf(V, FS) plots the temporal power spectrum, spatially averaged, of the time series of vector or scalar fields V. FS is the sampling frequency, in Hz (1 Hz by default). The maximum frenquency is half the sampling frequency (Nyquist theorem). Points containing zero or NaN values in their time series are not taken into account (use the option 'zero' to include them) tempspecf(V, FS, 'Property1', 'Property2', ...) specifies the properties: - 'hann': uses a Hann apodization. - 'peak': also shows the frequency and index of the highest peaks. - 'doublex' or 'doubley': for 2-component velocity fields, counts twice the energy spectrum for the x (or y) velocity component (useful in case of statistical axisymmetry). - 'zero': include the points containing zero or NaN values. [W, E] = tempspecf(...) returns the result without display, where W = 2*pi*F is the radian frequency (rad/s) and E the energy density. Method: each point (i,j) of the fields give a time series. The temporal spectra of each of those time series are computed, and averaged over all points (i,j). By default, if the time series of a point (i,j) contains at least one zero or NaN value, the corresponding spectrum is not computed (unless the option 'zero' is specified). Example tempspecf (v, 2, 'hann', 'peak'); Parseval theorem (energy conservation) verification, for 2-components fields: [w,e] = tempspecf(v,1); energy_spectral = sum(e)*w(2); [sx, sy] = statf(v); energy_physical = sx.rms^2 + sy.rms^2; Note: for fields containing zero and/or NaN values, the Parseval theorem is not satisfied. See Also tempfilterf, tempcorrf, spatiotempcorrf, specf Published output in the Help browser showdemo tempspecf ```
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