TDP time-domain parameters extracts EEG features very fast (low computational efforts) This is function was motivated by the Hjorth and Barlow parameters and is experimental. [F,G] = TDP(...) [...] = tdp(S,p,0) calculates the log-power of the first p-th derivatives [...] = tdp(S,p,UC) with 0<UC<1, calculates time-varying power of the first p-th derivatives using an exponential window [...] = tdp(S,p,N) with N>1, calculates time-varying log-power of the first p-th derivatives using rectangulare window of length N [...] = tdp(S,p,B,A) with B>=1 oder length(B)>1, calculates time-varying log-power of the first p-th derivatives using the transfer function B(z)/A(z) for windowing Input: S data (each channel is a column) p number of features UC update coefficient B,A filter coefficients (window function) Output: F log-power of each channel and each derivative in case of p=2, this is a linear combination of log(hjorth) G log-amplitude of each channel and each derivative in case of p=2, this is a linear combination of log(barlow) Relationship to related parameters: Hjorth's ACTIVITY = exp(F(:,1)); Hjorth's MOBILITY = exp(F(:,2)-F(:,1))/2; Hjorth's COMPLEXITY = exp(F(:,3)-F(:,2))/2; LINELENGTH = exp(G(:,2)); AREA = exp(G(:,1)); Barlow's AMPLITUDE = exp(G(:,1)) = AREA; Barlow's FREQUENCY = exp(G(:,2)-G(:,1)); Barlow's Spectral Purity Index SPI = exp(2*F(:,2)-F(:,1)-F(:,3)) see also: HJORTH, BARLOW, WACKERMANN REFERENCE(S): [1] B. Hjorth, EEG analysis based on time domain properties Electroencephalography and Clinical Neurophysiology, vol. 29, no. 3, pp. 306–310, September 1970. [2] B. Hjorth, Time Domain Descriptors and their Relation to particulare Model for Generation of EEG activity. in G. Dolce, H. Kunkel: CEAN Computerized EEG Analysis, Gustav Fischer 1975, S.3-8. [3] Goncharova II, Barlow JS. Changes in EEG mean frequency and spectral purity during spontaneous alpha blocking. Electroencephalogr Clin Neurophysiol. 1990 Sep;76(3):197-204.

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