diff --git a/lib/matplotlib/mlab.py b/lib/matplotlib/mlab.py index d0fcacb74028..05b251d1644d 100644 --- a/lib/matplotlib/mlab.py +++ b/lib/matplotlib/mlab.py @@ -1239,78 +1239,65 @@ def specgram(x, NFFT=None, Fs=None, detrend=None, window=None, """ Compute a spectrogram. - Call signature:: - - specgram(x, NFFT=256, Fs=2,detrend=mlab.detrend_none, - window=mlab.window_hanning, noverlap=128, - cmap=None, xextent=None, pad_to=None, sides='default', - scale_by_freq=None, mode='default') - - Compute and plot a spectrogram of data in *x*. Data are split into - *NFFT* length segments and the spectrum of each section is - computed. The windowing function *window* is applied to each + Compute and plot a spectrogram of data in x. Data are split into + NFFT length segments and the spectrum of each section is + computed. The windowing function window is applied to each segment, and the amount of overlap of each segment is - specified with *noverlap*. + specified with noverlap. - *x*: 1-D array or sequence - Array or sequence containing the data + Parameters + ---------- + x : array_like + 1-D array or sequence. %(Spectral)s %(PSD)s - *mode*: [ 'default' | 'psd' | 'complex' | 'magnitude' - 'angle' | 'phase' ] - - What sort of spectrum to use. Default is 'psd'. which takes the - power spectral density. 'complex' returns the complex-valued - frequency spectrum. 'magnitude' returns the magnitude spectrum. - 'angle' returns the phase spectrum without unwrapping. 'phase' - returns the phase spectrum with unwrapping. - - *noverlap*: integer - The number of points of overlap between blocks. The default value - is 128. - - Returns the tuple (*spectrum*, *freqs*, *t*): + noverlap : int, optional + The number of points of overlap between blocks. The default + value is 128. + mode : str, optional + What sort of spectrum to use, default is 'psd'. + 'psd' + Returns the power spectral density. - *spectrum*: 2-D array - columns are the periodograms of successive segments + 'complex' + Returns the complex-valued frequency spectrum. - *freqs*: 1-D array - The frequencies corresponding to the rows in *spectrum* - - *t*: 1-D array - The times corresponding to midpoints of segments (i.e the columns - in *spectrum*). + 'magnitude' + Returns the magnitude spectrum. - .. note:: + 'angle' + Returns the phase spectrum without unwrapping. - *detrend* and *scale_by_freq* only apply when *mode* is set to - 'psd' + 'phase' + Returns the phase spectrum with unwrapping. - .. seealso:: + Returns + ------- + spectrum : array_like + 2-D array, columns are the periodograms of successive segments. - :func:`psd` - :func:`psd` differs in the default overlap; in returning - the mean of the segment periodograms; and in not returning - times. + freqs : array_like + 1-D array, frequencies corresponding to the rows in *spectrum*. - :func:`complex_spectrum` - A single spectrum, similar to having a single segment when - *mode* is 'complex'. + t : array_like + 1-D array, the times corresponding to midpoints of segments + (i.e the columns in *spectrum*). - :func:`magnitude_spectrum` - A single spectrum, similar to having a single segment when - *mode* is 'magnitude'. + See Also + -------- + psd : differs in the overlap and in the return values. + complex_spectrum : similar, but with complex valued frequencies. + magnitude_spectrum : similar single segment when mode is 'magnitude'. + angle_spectrum : similar to single segment when mode is 'angle'. + phase_spectrum : similar to single segment when mode is 'phase'. - :func:`angle_spectrum` - A single spectrum, similar to having a single segment when - *mode* is 'angle'. + Notes + ----- + detrend and scale_by_freq only apply when *mode* is set to 'psd'. - :func:`phase_spectrum` - A single spectrum, similar to having a single segment when - *mode* is 'phase'. """ if noverlap is None: noverlap = 128