tdp

  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.