Determine the effect of an end-to-end mismatch on the autocorrelation structure for various sub-sequence lenths. It is important to avoid jumps and phase slips that occur when the data is periodically continued when making Fourier based surrogates, e.g. with surrogates.
-o output file name, just -o means file_end
-l number of points (whole file)
-x number of values to be skipped (0)
-m number of columns to be read (1)
-c columns to be read (1)
-V verbosity level (0 = only fatal errors)
-h show this message
The mismatch in value is measured by
/ \ 2 | x(1)-x(N) | \ / d = __________________ jump __ \ / _ \ 2 | | x(n)-x | /__ \ /and the phase slip by
/ \ 2 | (x(2)-x(1))-(x(N)-x(N-1)) | \ / d = _________________________________ slip __ . \ / _ \ 2 | | x(n)-x | /__ \ /The weighted mismatch is then
j*d + (1-j)*d . jump slipIn the multivariate case, the values of d are computed for each channel seperately and then averaged.
The sub-sequence length is successively decreased, only considering lengths which can be factorized with factors 2, 3 and 5 (that is what surrogates can handle). For each length, the optimal time offset is determined and a result is printed whenever an improvement was found. You can then use the -x and -l options to choose that sub-sequence for surrogates.
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