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- function [S,t,f,R,Serr]=mtspecgrampb(data,movingwin,params,fscorr)
- % 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 one of the following
- % forms:
- % (1) A numeric vector [TW K] where TW is the
- % time-bandwidth product and K is the number of
- % tapers to be used (less than or equal to
- % 2TW-1).
- % (2) A numeric vector [W T p] where W is the
- % bandwidth, T is the duration of the data and p
- % is an integer such that 2TW-p tapers are used. In
- % this form there is no default i.e. to specify
- % the bandwidth, you have to specify T and p as
- % well. Note that the units of W and T have to be
- % consistent: if W is in Hz, T must be in seconds
- % and vice versa. Note that these units must also
- % be consistent with the units of params.Fs: W can
- % be in Hz if and only if params.Fs is in Hz.
- % The default is to use form 1 with TW=3 and K=5
- % Note that T has to be equal to movingwin(1).
- %
- % 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
- if nargin < 2; error('Need data and window parameters'); end;
- if nargin < 3; params=[]; end;
- [tapers,pad,Fs,fpass,err,trialave,params]=getparams(params);
- if length(params.tapers)==3 & movingwin(1)~=params.tapers(2);
- error('Duration of data in params.tapers is inconsistent with movingwin(1), modify params.tapers(2) to proceed')
- end
- if nargin < 4 || isempty(fscorr); fscorr=0; end;
- if nargout > 4 && err(1)==0;
- % error('Cannot compute errors with err(1)=0');
- error('When Serr is desired, err(1) has to be non-zero.');
- end;
- data=change_row_to_column(data);
- [N,Ch]=size(data);
- Nwin=round(Fs*movingwin(1)); % number of samples in window
- Nstep=round(movingwin(2)*Fs); % number of samples to step through
- nfft=max(2^(nextpow2(Nwin)+pad),Nwin);
- f=getfgrid(Fs,nfft,fpass); Nf=length(f);
- params.tapers=dpsschk(tapers,Nwin,Fs); % check tapers
- winstart=1:Nstep:N-Nwin+1;
- nw=length(winstart);
- if trialave
- S = zeros(nw,Nf);
- R = zeros(nw,Nwin);
- if nargout==4; Serr=zeros(2,nw,Nf); end;
- else
- S = zeros(nw,Nf,Ch);
- R = zeros(nw,Nwin,Ch);
- if nargout==4; Serr=zeros(2,nw,Nf,Ch); end;
- end
- for n=1:nw;
- indx=winstart(n):winstart(n)+Nwin-1;
- datawin=data(indx,:);
- if nargout==5;
- [s,f,r,serr]=mtspectrumpb(datawin,params,fscorr);
- Serr(1,n,:,:)=squeeze(serr(1,:,:));
- Serr(2,n,:,:)=squeeze(serr(2,:,:));
- else
- [s,f,r]=mtspectrumpb(datawin,params,fscorr);
- end;
- S(n,:,:)=s;
- R(n,:)=r';
- end;
- winmid=winstart+round(Nwin/2);
- t=winmid/Fs;
- S=squeeze(S); R=squeeze(R); if nargout==5; Serr=squeeze(Serr);end
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