coherencypb

PURPOSE ^

Multi-taper coherency - binned point process

SYNOPSIS ^

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

DESCRIPTION ^

 Multi-taper coherency - binned point process

 Usage:

 [C,phi,f,confC,phierr,Cerr]=coherencypb(data1,data2,tapers,pad,Fs,fpass,err,trialave,fscorr)
 Input: 
       data1 (in form samples x channels/trials) -- required
       data2 (in form samples x channels/trials) -- 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   (binning 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)
       f (frequencies)     
       confC (confidence level for c at 1-p %)
       phierr (error bars for phi)
       Cerr  (error bars for C)

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:

SOURCE CODE ^

0001 function [C,phi,f,confC,phierr,Cerr]=coherencypb(data1,data2,tapers,pad,Fs,fpass,err,trialave,fscorr)
0002 % Multi-taper coherency - binned point process
0003 %
0004 % Usage:
0005 %
0006 % [C,phi,f,confC,phierr,Cerr]=coherencypb(data1,data2,tapers,pad,Fs,fpass,err,trialave,fscorr)
0007 % Input:
0008 %       data1 (in form samples x channels/trials) -- required
0009 %       data2 (in form samples x channels/trials) -- required
0010 %       tapers (precalculated tapers from dpss, or in the form [NW K] e.g [3 5]) -- optional. If not
0011 %                                                 specified, use [NW K]=[3 5]
0012 %        pad            (padding factor for the FFT) - optional. Defaults to 0.
0013 %                       e.g. For N = 500, if PAD = 0, we pad the FFT
0014 %                       to 512 points; if PAD = 2, we pad the FFT
0015 %                       to 2048 points, etc.
0016 %       Fs   (binning frequency) - optional. Default 1.
0017 %       fpass    (frequency band to be used in the calculation in the form
0018 %                                   [fmin fmax])- optional.
0019 %                                   Default all frequencies between 0 and Fs/2
0020 %       err  (error calculation [1 p] - Theoretical error bars; [2 p] - Jackknife error bars
0021 %                                   [0 p] or 0 - no error bars) - optional. Default 0.
0022 %       trialave (average over trials when 1, don't average when 0) - optional. Default 0
0023 %       fscorr   (finite size corrections, 0 (don't use finite size corrections) or 1 (use finite size corrections) - optional
0024 %                (available only for spikes). Defaults 0.
0025 % Output:
0026 %       C (abs of coherency frequency index x channels/trials)
0027 %       phi (phase of coherency frequency x channels/trials)
0028 %       f (frequencies)
0029 %       confC (confidence level for c at 1-p %)
0030 %       phierr (error bars for phi)
0031 %       Cerr  (error bars for C)
0032 warning off MATLAB:divideByZero
0033 if nargin < 2; error('Need data1 and data2'); end;
0034 [N,C]=size(data1);
0035 if nargin < 3; tapers=[3 5]; end;
0036 if nargin < 4;pad=0;end;
0037 if nargin < 5; Fs=1; end;
0038 if nargin < 6; fpass=[0 Fs/2]; end;
0039 if nargin < 7; err=0; end;
0040 if nargin < 8; trialave=0;end;
0041 if nargin < 9; fscorr=0; end;
0042 
0043 if isempty(tapers); tapers=[3 5]; end;
0044 if isempty(pad);pad=0;end;
0045 if isempty(Fs); Fs=1; end;
0046 if isempty(fpass); fpass=[0 Fs/2]; end;
0047 if isempty(err); err=0; end;
0048 if isempty(trialave); trialave=0;end;
0049 if isempty(fscorr);fscorr=0;end;
0050 
0051 if nargout > 5 & err(1)~=2; 
0052     error('Cerr computed only for Jackknife. Correct inputs and run again');
0053 end;
0054 
0055 nfft=2^(nextpow2(N)+pad);
0056 [f,findx]=getfgrid(Fs,nfft,fpass); 
0057 tapers=dpsschk(tapers,N); % check tapers
0058 [J1,Msp1,Nsp1]=mtfftpb(data1,tapers,nfft);
0059 [J2,Msp2,Nsp2]=mtfftpb(data2,tapers,nfft);
0060 J1=J1(findx,:,:);
0061 J2=J2(findx,:,:);
0062 S12=squeeze(mean(conj(J1).*J2,2));
0063 S1=squeeze(mean(conj(J1).*J1,2));
0064 S2=squeeze(mean(conj(J2).*J2,2));
0065 C12=S12./sqrt(S1.*S2);
0066 if trialave==1; C12=squeeze(mean(C12,2));end;
0067 C=abs(C12);
0068 phi=angle(C12);
0069 if nargout==6; 
0070     if fscorr==1; 
0071        [confC,phierr,Cerr]=coherr(C,J1,J2,err,trialave,Nsp1,Nsp2);
0072     else;
0073        [confC,phierr,Cerr]=coherr(C,J1,J2,err,trialave);
0074     end;
0075 elseif nargout==5;
0076     if fscorr==1; 
0077         [confC,phierr]=coherr(C,J1,J2,err,trialave,Nsp1,Nsp2);
0078     else;
0079         [confC,phierr]=coherr(C,J1,J2,err,trialave);
0080     end;
0081 end;

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