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- function [S,f,R,Serr]=mtspectrumpb(data,params,fscorr)
- % Multi-taper spectrum - binned point process
- %
- % Usage:
- %
- % [S,f,R,Serr]=mtspectrumpb(data,params,fscorr)
- % Input:
- % data (in form samples x channels/trials or a single vector) -- required
- % 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
- %
- % 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 channels/trials 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 frequency x channels/trials if trialave=0;
- % as a function of frequency if trialave=1)
- % f (frequencies)
- % R (spike rate)
- % Serr (error bars) - only for err(1)>=1
- if nargin < 1; error('Need data'); end;
- if nargin < 2; params=[]; end;
- [tapers,pad,Fs,fpass,err,trialave,params]=getparams(params);
- clear params
- if nargout > 3 && err(1)==0;
- % Cannot compute error bars with err(1)=0. Need to change params and run again
- error('When Serr is desired, err(1) has to be non-zero.');
- end;
- if nargin < 3 || isempty(fscorr); fscorr=0;end;
- data=change_row_to_column(data);
- N=size(data,1);
- nfft=max(2^(nextpow2(N)+pad),N);
- [f,findx]=getfgrid(Fs,nfft,fpass);
- tapers=dpsschk(tapers,N,Fs); % check tapers
- [J,Msp,Nsp]=mtfftpb(data,tapers,nfft);
- J=J(findx,:,:);
- S=squeeze(mean(conj(J).*J,2));
- if trialave; S=squeeze(mean(S,2)); Msp=mean(Msp);end;
- R=Msp*Fs;
- if nargout==4;
- if fscorr==1;
- Serr=specerr(S,J,err,trialave,Nsp);
- else
- Serr=specerr(S,J,err,trialave);
- end;
- end;
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