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reference:ft_freqdescriptives [2018/08/23 14:43] (current)
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 +Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_freqdescriptives"​.
 +  <a href=/​reference/​ft_freqdescriptives><​font color=green>​FT_FREQDESCRIPTIVES</​font></​a>​ 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 <a href=/​reference/​ft_freqanalysis><​font color=green>​FT_FREQANALYSIS</​font></​a>​ or <a href=/​reference/​ft_mvaranalysis><​font color=green>​FT_MVARANALYSIS</​font></​a>​ 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 <a href=/​reference/​ft_channelselection><​font color=green>​FT_CHANNELSELECTION</​font></​a>​ 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 <a href=/​reference/​ft_connectivityanalysis><​font color=green>​FT_CONNECTIVITYANALYSIS</​font></​a>​.
 +  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 <a href=/​reference/​ft_freqanalysis><​font color=green>​FT_FREQANALYSIS</​font></​a>,​ <a href=/​reference/​ft_freqstatistics><​font color=green>​FT_FREQSTATISTICS</​font></​a>,​ <a href=/​reference/​ft_freqbaseline><​font color=green>​FT_FREQBASELINE</​font></​a>,​ <a href=/​reference/​ft_connectivityanalysis><​font color=green>​FT_CONNECTIVITYANALYSIS</​font></​a>​