FieldTrip

Note that this reference documentation is identical to the help that is displayed in Matlab when you type “help ft_connectivity_corr”.

  FT_CONNECTIVITY_CORR computes correlation or coherence from a data-matrix
  containing a covariance or cross-spectral density.
 
  Use as
    [c, v, n] = ft_connectivity_corr(input, varargin)
  
  The input data input should be organized as:
    Repetitions x Channel x Channel (x Frequency) (x Time)
  or
    Repetitions x Channelcombination (x Frequency) (x Time)
  
  The first dimension should be singleton if the input already contains
  an average. Furthermore, the input data can be complex-valued cross
  spectral densities, or real-valued covariance estimates. If the former
  is the case, the output will be coherence (or a derived metric), if the
  latter is the case, the output will be the correlation coefficient.
 
  Additional input arguments come as key-value pairs:
 
  hasjack  0 or 1 specifying whether the Repetitions represent
                    leave-one-out samples
  complex  'abs', 'angle', 'real', 'imag', 'complex', 'logabs' for 
                    post-processing of coherency
  feedback 'none', 'text', 'textbar' type of feedback showing progress of
                    computation
  dimord          specifying how the input matrix should be interpreted
  powindx         required if the input data contain linearly indexed 
                    channel pairs. should be an Nx2 matrix indexing on each 
                    row for the respective channel pair the indices of the 
                    corresponding auto-spectra
  pownorm         flag that specifies whether normalisation with the product
                    of the power should be performed (thus should be true when
                    correlation/coherence is requested, and false when covariance
                    or cross-spectral density is requested).
 
  Partialisation can be performed when the input data is (chan x chan).
  The following options need to be specified: 
  
  pchanindx       index-vector to the channels that need to be partialised 
  allchanindx     index-vector to all channels that are used (including the 
                   "to-be-partialised" ones).
 
  The output c contains the correlation/coherence, v is a variance estimate
  which only can be computed if the data contains leave-one-out samples,
  and n is the number of repetitions in the input data.
  
  See also FT_CONNECTIVITYANALYSIS