Creates surrogate time series using Fourier surrogates
fftsurrog(dat, nsurrogs, syncpres)A locations x time matrix of observations
The number of surrogates to produce
Logical. TRUE for "synchrony preserving" surrogates (same phase randomizations used for all time series). FALSE leads to independent phase randomizations for all time series.
fftsurrog returns a list of nsurrogs surrogate datasets
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Prichard, D and Theiler, J (1994) Generating surrogate data for time series with several simultaneously measured variables. Physical Review Letters 73, 951-954.