Home > chronux_1_50 > pointbinned > mtspecgrampb.m

mtspecgrampb

PURPOSE ^

Multi-taper time-frequency spectrum - binned point process

SYNOPSIS ^

function [S,t,f,R,Serr]=mtspecgrampb(data,movingwin,params,fscorr)

DESCRIPTION ^

 Multi-taper time-frequency spectrum - binned point process

 Usage:

 [S,t,f,R,Serr]=mtspecgrampb(data,movingwin,params,fscorr)
 Input: 
       data        (in form samples x channels/trials or single vector) -- required
       movingwin         (in the form [window,winstep] i.e length of moving
                                                 window and step size.
                                                 
       params: structure with fields tapers, pad, Fs, fpass, err, trialave
       - optional
           tapers (precalculated tapers from dpss, or in the form [NW K] e.g [3 5]) -- optional. If not 
                                                 specified, use [NW K]=[3 5]
            pad            (padding factor for the FFT) - optional (can take values -1,0,1,2...). 
                    -1 corresponds to no padding, 0 corresponds to padding
                    to the next highest power of 2 etc.
                       e.g. For N = 500, if PAD = -1, we do not pad; if PAD = 0, we pad the FFT
                       to 512 points, if pad=1, we pad to 1024 points etc.
                       Defaults to 0.
           Fs   (sampling frequency) - optional. Default 1.
           fpass    (frequency band to be used in the calculation in the form
                                   [fmin fmax])- optional. 
                                   Default all frequencies between 0 and Fs/2
           err  (error calculation [1 p] - Theoretical error bars; [2 p] - Jackknife error bars
                                   [0 p] or 0 - no error bars) - optional. Default 0.
           trialave (average over trials/channnels when 1, don't average when 0) - optional. Default 0
       fscorr   (finite size corrections, 0 (don't use finite size corrections) or 1 (use finite size corrections) - optional
                (available only for spikes). Defaults 0.
 Output:
       S       (spectrum in form time x frequency x channels/trials for trialave=0; or as a function of frequency if trialave=1)
       t       (times)
       f       (frequencies)
       R       (rate)
       Serr    (error bars) - only for err(1)>=1

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:

SOURCE CODE ^

0001 function [S,t,f,R,Serr]=mtspecgrampb(data,movingwin,params,fscorr)
0002 % Multi-taper time-frequency spectrum - binned point process
0003 %
0004 % Usage:
0005 %
0006 % [S,t,f,R,Serr]=mtspecgrampb(data,movingwin,params,fscorr)
0007 % Input:
0008 %       data        (in form samples x channels/trials or single vector) -- required
0009 %       movingwin         (in the form [window,winstep] i.e length of moving
0010 %                                                 window and step size.
0011 %
0012 %       params: structure with fields tapers, pad, Fs, fpass, err, trialave
0013 %       - optional
0014 %           tapers (precalculated tapers from dpss, or in the form [NW K] e.g [3 5]) -- optional. If not
0015 %                                                 specified, use [NW K]=[3 5]
0016 %            pad            (padding factor for the FFT) - optional (can take values -1,0,1,2...).
0017 %                    -1 corresponds to no padding, 0 corresponds to padding
0018 %                    to the next highest power of 2 etc.
0019 %                       e.g. For N = 500, if PAD = -1, we do not pad; if PAD = 0, we pad the FFT
0020 %                       to 512 points, if pad=1, we pad to 1024 points etc.
0021 %                       Defaults to 0.
0022 %           Fs   (sampling frequency) - optional. Default 1.
0023 %           fpass    (frequency band to be used in the calculation in the form
0024 %                                   [fmin fmax])- optional.
0025 %                                   Default all frequencies between 0 and Fs/2
0026 %           err  (error calculation [1 p] - Theoretical error bars; [2 p] - Jackknife error bars
0027 %                                   [0 p] or 0 - no error bars) - optional. Default 0.
0028 %           trialave (average over trials/channnels when 1, don't average when 0) - optional. Default 0
0029 %       fscorr   (finite size corrections, 0 (don't use finite size corrections) or 1 (use finite size corrections) - optional
0030 %                (available only for spikes). Defaults 0.
0031 % Output:
0032 %       S       (spectrum in form time x frequency x channels/trials for trialave=0; or as a function of frequency if trialave=1)
0033 %       t       (times)
0034 %       f       (frequencies)
0035 %       R       (rate)
0036 %       Serr    (error bars) - only for err(1)>=1
0037 
0038 if nargin < 2; error('Need data and window parameters'); end;
0039 if nargin < 3; params=[]; end;
0040 [tapers,pad,Fs,fpass,err,trialave,params]=getparams(params);
0041 
0042 if nargin < 4 || isempty(fscorr); fscorr=0; end;
0043 if nargout > 4 && err(1)==0; 
0044 %    error('Cannot compute errors with err(1)=0');
0045      error('When Serr is desired, err(1) has to be non-zero.');
0046 end;
0047 data=change_row_to_column(data);
0048 [N,Ch]=size(data);
0049 Nwin=round(Fs*movingwin(1)); % number of samples in window
0050 Nstep=round(movingwin(2)*Fs); % number of samples to step through
0051 nfft=max(2^(nextpow2(Nwin)+pad),Nwin);
0052 f=getfgrid(Fs,nfft,fpass); Nf=length(f);
0053 params.tapers=dpsschk(tapers,Nwin,Fs); % check tapers
0054 winstart=1:Nstep:N-Nwin+1;
0055 nw=length(winstart);
0056 if trialave
0057     S = zeros(nw,Nf);
0058     R = zeros(nw,Nwin);
0059     if nargout==4; Serr=zeros(2,nw,Nf); end;
0060 else
0061     S = zeros(nw,Nf,Ch);
0062     R = zeros(nw,Nwin,Ch);
0063     if nargout==4; Serr=zeros(2,nw,Nf,Ch); end;
0064 end
0065 
0066 for n=1:nw;
0067    indx=winstart(n):winstart(n)+Nwin-1;
0068    datawin=data(indx,:);
0069    if nargout==5;
0070      [s,f,r,serr]=mtspectrumpb(datawin,params,fscorr);
0071      Serr(1,n,:,:)=squeeze(serr(1,:,:));
0072      Serr(2,n,:,:)=squeeze(serr(2,:,:));
0073    else
0074      [s,f,r]=mtspectrumpb(datawin,params,fscorr);
0075    end;
0076    S(n,:,:)=s;
0077    R(n,:)=r';
0078 end;
0079 winmid=winstart+round(Nwin/2);
0080 t=winmid/Fs;
0081 S=squeeze(S); R=squeeze(R); if nargout==5; Serr=squeeze(Serr);end

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