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- function [C,phi,S12,S1,S2,f,zerosp,confC,phistd,Cerr]=coherencycpb(data1,data2,params,fscorr)
- % Multi-taper coherency,cross-spectrum and individual spectra - continuous and binned point process data
- %
- % Usage:
- %
- % [C,phi,S12,S1,S2,f,zerosp,confC,phistd,Cerr]=coherencycpb(data1,data2,params,fscorr)
- % Inputs:
- % data1 (continuous data in form samples x trials) -- required
- % data2 (binned spike data in form samples x trials) -- 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 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.
- % Outputs:
- % C (magnitude of coherency - frequencies x trials if trialave=0; dimension frequencies if trialave=1)
- % phi (phase of coherency - frequencies x trials if trialave=0; dimension frequencies if trialave=1)
- % S12 (cross spectrum - frequencies x trials if trialave=0; dimension frequencies if trialave=1)
- % S1 (spectrum 1 - frequencies x trials if trialave=0; dimension frequencies if trialave=1)
- % S2 (spectrum 2 - frequencies x trials if trialave=0; dimension frequencies if trialave=1)
- % f (frequencies)
- % zerosp (1 for trials where no spikes were found, 0 otherwise)
- % confC (confidence level for C at 1-p %) - only for err(1)>=1
- % phistd - theoretical/jackknife (depending on err(1)=1/err(1)=2) standard deviation for phi
- % Note that phi + 2 phistd and phi - 2 phistd will give 95% confidence
- % bands for phi - only for err(1)>=1
- % Cerr (Jackknife error bars for C - use only for Jackknife - err(1)=2)
- if nargin < 2; error('Need data1 and data2'); end
- if nargin < 3; params=[]; end;
- [tapers,pad,Fs,fpass,err,trialave,params]=getparams(params);
- clear params
- if nargin < 4 || isempty(fscorr); fscorr=0; end;
- if nargout > 7 && err(1)==0;
- %Cannot compute error bars if err(1)=0. Need to change params and run again.
- error('When errors are desired, err(1) has to be non-zero.');
- end;
- if nargout > 9 && err(1)~=2;
- error('Cerr computed only for Jackknife. Correct inputs and run again');
- end;
- [N,Ch]=check_consistency(data1,data2);
- zerosp=zeros(1,Ch); % intialize the zerosp variable
- nfft=max(2^(nextpow2(N)+pad),N);
- [f,findx]=getfgrid(Fs,nfft,fpass);
- tapers=dpsschk(tapers,N,Fs); % check tapers
- J1=mtfftc(data1,tapers,nfft,Fs); % fourier transform of continuous data
- [J2,Msp2,Nsp2]=mtfftpb(data2,tapers,nfft); % fourier transform of point process data
- zerosp(Nsp2==0)=1; % set the trials where no spikes were found to have zerosp=1
- J1=J1(findx,:,:);
- J2=J2(findx,:,:);
- S12=squeeze(mean(conj(J1).*J2,2));
- S1=squeeze(mean(conj(J1).*J1,2));
- S2=squeeze(mean(conj(J2).*J2,2));
- if trialave; S12=squeeze(mean(S12,2)); S1=squeeze(mean(S1,2)); S2=squeeze(mean(S2,2)); end;
- C12=S12./sqrt(S1.*S2);
- C=abs(C12);
- phi=angle(C12);
- if nargout==10;
- if fscorr==1;
- [confC,phistd,Cerr]=coherr(C,J1,J2,err,trialave,[],Nsp2);
- else
- [confC,phistd,Cerr]=coherr(C,J1,J2,err,trialave);
- end;
- elseif nargout==9;
- if fscorr==1;
- [confC,phistd]=coherr(C,J1,J2,err,trialave,[],Nsp2);
- else
- [confC,phistd]=coherr(C,J1,J2,err,trialave);
- end;
- end;
- clear Msp2
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