cohgrampb

PURPOSE ^

Multi-taper time-frequency coherence - two binned point processes

SYNOPSIS ^

function [C,phi,t,f,confC,phierr,Cerr]=cohgrampb(data1,data2,movingwin,tapers,pad,Fs,fpass,err,trialave,fscorr)

DESCRIPTION ^

 Multi-taper time-frequency coherence - two binned point processes
 process 

 Usage:

 [C,phi,t,f,confC,phierr,Cerr]=cohgrampb(data1,data2,movingwin,tapers,nfft,Fs,fpass,err,trialave)
 Input: 
 Note units have to be consistent. Thus, if movingwin is in seconds, Fs
 has to be in Hz. see chronux.m for more information.

       data1 (binned point process data in form samples x channels/trials) -- required
       data2 (binned point process data in form samples x channels/trials) -- required
       movingwin (in the form [window winstep] -- required
       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. Defaults to 0.  
                       e.g. For N = 500, if PAD = 0, we pad the FFT 
                       to 512 points; if PAD = 2, we pad the FFT
                       to 2048 points, etc.
       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.
 Output:
       C (abs of coherency frequency index x channels/trials)
       phi (phase of coherency frequency x channels/trials)
       t (time)
       f (frequencies)
       confC (confidence level for c at 1-p %)
       phierr (error bars for phi)
       Cerr  (Jackknife error bars for C - use only for Jackknife)

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:

SOURCE CODE ^

0001 function [C,phi,t,f,confC,phierr,Cerr]=cohgrampb(data1,data2,movingwin,tapers,pad,Fs,fpass,err,trialave,fscorr)
0002 % Multi-taper time-frequency coherence - two binned point processes
0003 % process
0004 %
0005 % Usage:
0006 %
0007 % [C,phi,t,f,confC,phierr,Cerr]=cohgrampb(data1,data2,movingwin,tapers,nfft,Fs,fpass,err,trialave)
0008 % Input:
0009 % Note units have to be consistent. Thus, if movingwin is in seconds, Fs
0010 % has to be in Hz. see chronux.m for more information.
0011 %
0012 %       data1 (binned point process data in form samples x channels/trials) -- required
0013 %       data2 (binned point process data in form samples x channels/trials) -- required
0014 %       movingwin (in the form [window winstep] -- required
0015 %       tapers (precalculated tapers from dpss, or in the form [NW K] e.g [3 5]) -- optional. If not
0016 %                                                 specified, use [NW K]=[3 5]
0017 %        pad            (padding factor for the FFT) - optional. Defaults to 0.
0018 %                       e.g. For N = 500, if PAD = 0, we pad the FFT
0019 %                       to 512 points; if PAD = 2, we pad the FFT
0020 %                       to 2048 points, etc.
0021 %       Fs   (sampling frequency) - optional. Default 1.
0022 %       fpass    (frequency band to be used in the calculation in the form
0023 %                                   [fmin fmax])- optional.
0024 %                                   Default all frequencies between 0 and Fs/2
0025 %       err  (error calculation [1 p] - Theoretical error bars; [2 p] - Jackknife error bars
0026 %                                   [0 p] or 0 - no error bars) - optional. Default 0.
0027 %       trialave (average over trials when 1, don't average when 0) - optional. Default 0
0028 %       fscorr   (finite size corrections, 0 (don't use finite size corrections) or 1 (use finite size corrections) - optional
0029 %                (available only for spikes). Defaults 0.
0030 % Output:
0031 %       C (abs of coherency frequency index x channels/trials)
0032 %       phi (phase of coherency frequency x channels/trials)
0033 %       t (time)
0034 %       f (frequencies)
0035 %       confC (confidence level for c at 1-p %)
0036 %       phierr (error bars for phi)
0037 %       Cerr  (Jackknife error bars for C - use only for Jackknife)
0038 
0039 if nargin < 3; error('Need data1 and data2 and window parameters'); end;
0040 [N1,C1]=size(data1);[N2,C2]=size(data2);
0041 if N1~=N2 | C1~=C2; error('data incompatible'); end;
0042 if nargin < 4; tapers=[3 5]; end;
0043 if nargin < 5;pad=0;end;
0044 if nargin < 6; Fs=1; end;
0045 if nargin < 7; fpass=[0 Fs/2]; end;
0046 if nargin < 8; err=0; end;
0047 if nargin < 9; trialave=0;end;
0048 if nargin < 10; fscorr=0;end;
0049 
0050 if isempty(tapers); tapers=[3 5]; end;
0051 if isempty(pad);pad=0;end;
0052 if isempty(Fs); Fs=1; end;
0053 if isempty(fpass); fpass=[0 Fs/2]; end;
0054 if isempty(err); err=0; end;
0055 if isempty(trialave); trialave=0;end;
0056 if isempty(fscorr);fscorr=0;end;
0057 
0058 if nargout > 6 & err(1)~=2; 
0059     error('Cerr computed only for Jackknife. Correct inputs and run again');
0060 end;
0061 Nwin=round(Fs*movingwin(1)); % number of samples in window
0062 Nstep=round(movingwin(2)*Fs); % number of samples to step through
0063 nfft=2^(nextpow2(Nwin)+pad);
0064 [f,findx]=getfgrid(Fs,nfft,fpass); 
0065 tapers=dpsschk(tapers,Nwin,Fs); % check tapers
0066 
0067 winstart=1:Nstep:N1-Nwin+1;
0068 nw=length(winstart);
0069 for n=1:nw;
0070    indx=winstart(n):winstart(n)+Nwin-1;
0071    datawin1=data1(indx,:);datawin2=data2(indx,:);
0072    if nargout==7;
0073      [c,ph,f,confc,phie,cerr]=coherencypb(datawin1,datawin2,tapers,pad,Fs,fpass,err,trialave,fscorr);
0074      confC=confc;
0075      phierr(1,n,:,:)=squeeze(phie(1,:,:));
0076      phierr(2,n,:,:)=squeeze(phie(2,:,:));
0077      Cerr(1,n,:,:)=squeeze(cerr(1,:,:));
0078      Cerr(2,n,:,:)=squeeze(cerr(2,:,:));
0079    elseif nargout==6;
0080      [c,ph,f,confc,phie]=coherencypb(datawin1,datawin2,tapers,pad,Fs,fpass,err,trialave,fscorr);
0081      confC=confc;
0082      phierr(1,n,:,:)=squeeze(phie(1,:,:));
0083      phierr(2,n,:,:)=squeeze(phie(2,:,:));
0084    else
0085      [c,ph,f]=coherencycpb(datawin1,datawin2,tapers,pad,Fs,fpass,err,trialave,fscorr);
0086    end;
0087    C(n,:,:)=c;
0088    phi(n,:,:)=ph;
0089 end;
0090 C=squeeze(C); phi=squeeze(phi);if nargout==7;Cerr=squeeze(Cerr);end;
0091 if nargout==6; phierr=squeeze(phierr);end
0092 winmid=winstart+round(Nwin/2);
0093 t=winmid/Fs;

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