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 — reference:ft_freqdescriptives [2018/08/23 14:43] (current) Line 1: Line 1: + =====  FT_FREQDESCRIPTIVES ===== + + Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_freqdescriptives"​. + + <​html><​pre>​ + <​font color=green>​FT_FREQDESCRIPTIVES​ computes descriptive univariate statistics of + the frequency or time-frequency decomposition of the EEG/MEG signal, + thus the powerspectrum and its standard error. + + Use as + [freq] = ft_freqdescriptives(cfg,​ freq) + [freq] = ft_freqdescriptives(cfg,​ freqmvar) + + The data in freq should be organised in a structure as obtained from + from the <​font color=green>​FT_FREQANALYSIS​ or <​font color=green>​FT_MVARANALYSIS​ function. The output structure is comparable + to the input structure and can be used in most functions that require + a freq input. + + The configuration options are + cfg.variance ​     = '​yes'​ or '​no',​ estimate standard error in the standard way (default = '​no'​) + cfg.jackknife ​    = '​yes'​ or '​no',​ estimate standard error by means of the jack-knife (default = '​no'​) + cfg.keeptrials ​   = '​yes'​ or '​no',​ estimate single trial power (useful for fourier data) (default = '​no'​) + cfg.channel ​      = Nx1 cell-array with selection of channels (default = '​all'​),​ + see <​font color=green>​FT_CHANNELSELECTION​ for details + cfg.trials ​       = '​all'​ or a selection given as a 1xN vector (default = '​all'​) + cfg.frequency ​    = [fmin fmax] or '​all',​ to specify a subset of frequencies (default = '​all'​) + cfg.latency ​      = [tmin tmax] or '​all',​ to specify a subset of latencies (default = '​all'​) + + A variance estimate can only be computed if results from trials and/or + tapers have been kept. + + Descriptive statistics of bivariate metrics is not computed by this function anymore. To this end you + should use <​font color=green>​FT_CONNECTIVITYANALYSIS​. + + To facilitate data-handling and distributed computing you can use + cfg.inputfile ​  ​= ​ ... + cfg.outputfile ​ =  ... + If you specify one of these (or both) the input data will be read from a *.mat + file on disk and/or the output data will be written to a *.mat file. These mat + files should contain only a single variable, corresponding with the + input/​output structure. + + See also <​font color=green>​FT_FREQANALYSIS,​ <​font color=green>​FT_FREQSTATISTICS,​ <​font color=green>​FT_FREQBASELINE,​ <​font color=green>​FT_CONNECTIVITYANALYSIS​ +