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 reference:ft_connectivity_dtf [2018/08/23 14:43] reference:ft_connectivity_dtf [2018/08/23 14:43] (current) Line 1: Line 1: + =====  FT_CONNECTIVITY_DTF ===== + + Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_connectivity_dtf"​. + + <​html><​pre>​ + <​font color=green>​FT_CONNECTIVITY_DTF​ computes the directed transfer function. + + Use as + [d, v, n] = ft_connectivity_dtf(h,​ ...) + + The input data h should be a spectral transfer matrix organized as + Nrpt x Nchan x Nchan x Nfreq (x Ntime), + where Nrpt can be 1. + + Additional optional input arguments come as key-value pairs: + '​hasjack' ​ = 0 (default) is a boolean specifying whether the input + ​contains leave-one-outs,​ required for correct variance + ​estimate. + '​feedback'​ = string, determining verbosity (default = '​none'​),​ see <​font color=green>​FT_PROGRESS​ + '​crsspctrm'​ = matrix containing the cross-spectral density. If this + matrix is defined, the function + returns the ddtf, which requires an estimation of partial + coherence from this matrix. + '​invfun' ​  = '​inv'​ (default) or '​pinv',​ the function used to invert the + ​crsspctrm matrix to obtain the partial coherence. Pinv is + ​useful if the data are poorly-conditioned. + + + Output arguments: + d = partial directed coherence matrix Nchan x Nchan x Nfreq (x Ntime). + If multiple observations in the input, the average is returned. + v = variance of d across observations. + n = number of observations. + + Typically, nrpt should be 1 (where the spectral transfer matrix is computed across + observations. When nrpt&​gt;​1 and hasjack is true the input is assumed to contain the + leave-one-out estimates of H, thus a more reliable estimate of the relevant + quantities. + + See also <​font color=green>​FT_CONNECTIVITYANALYSIS​ +