


Multi-taper coherency matrix - point process times
Usage:
[C,phi,f,confC,phierr,Cerr]=cohmatrixpt(data,tapers,pad,Fs,fpass,err,fscorr)
Input:
data (structure array of spike times) - 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.
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)

0001 function [C,phi,f,confC,phierr,Cerr]=cohmatrixpt(data,tapers,pad,Fs,fpass,err,fscorr) 0002 % Multi-taper coherency matrix - point process times 0003 % 0004 % Usage: 0005 % 0006 % [C,phi,f,confC,phierr,Cerr]=cohmatrixpt(data,tapers,pad,Fs,fpass,err,fscorr) 0007 % Input: 0008 % data (structure array of spike times) - required 0009 % tapers (precalculated tapers from dpss, or in the form [NW K] e.g [3 5]) -- optional. If not 0010 % specified, use [NW K]=[3 5] 0011 % pad (padding factor for the FFT) - optional. Defaults to 0. 0012 % e.g. For N = 500, if PAD = 0, we pad the FFT 0013 % to 512 points; if PAD = 2, we pad the FFT 0014 % to 2048 points, etc. 0015 % Fs (binning frequency) - optional. Default 1. 0016 % fpass (frequency band to be used in the calculation in the form 0017 % [fmin fmax])- optional. 0018 % Default all frequencies between 0 and Fs/2 0019 % err (error calculation [1 p] - Theoretical error bars; [2 p] - Jackknife error bars 0020 % [0 p] or 0 - no error bars) - optional. Default 0. 0021 % fscorr (finite size corrections, 0 (don't use finite size corrections) or 1 (use finite size corrections) - optional 0022 % (available only for spikes). Defaults 0. 0023 % Output: 0024 % C (abs of coherency frequency index x channels/trials) 0025 % phi (phase of coherency frequency x channels/trials) 0026 % f (frequencies) 0027 % confC (confidence level for c at 1-p %) 0028 % phierr (error bars for phi) 0029 % Cerr (error bars for C) 0030 0031 if isstruct(data) 0032 Ch=length(data); 0033 if Ch==1; error('Need at least 2 channels'); end; 0034 else 0035 error('Need at least two channels of data in the a structural array'); 0036 end; 0037 if nargin < 2; tapers=[3 5]; end; 0038 if nargin < 3;pad=0;end; 0039 if nargin < 4; Fs=1; end; 0040 if nargin < 5; fpass=[0 Fs/2]; end; 0041 if nargin < 6; err=0; end; 0042 if nargin < 7; fscorr=0; end; 0043 0044 if isempty(tapers); tapers=[3 5]; end; 0045 if isempty(pad);pad=0;end; 0046 if isempty(Fs); Fs=1; end; 0047 if isempty(fpass); fpass=[0 Fs/2]; end; 0048 if isempty(err); err=0; end; 0049 if isempty(fscorr);fscorr=0;end 0050 0051 [mintime,maxtime]=minmaxsptimes(data); 0052 dt=1/Fs; % sampling time 0053 t=mintime:dt:maxtime+dt; % time grid for prolates 0054 N=length(t); % number of points in grid for dpss 0055 nfft=2^(nextpow2(N)+pad); % number of points in fft of prolates 0056 [f,findx]=getfgrid(Fs,nfft,fpass); % get frequency grid for evaluation 0057 tapers=dpsschk(tapers,N)*sqrt(Fs); % check tapers 0058 [J,Msp,Nsp]=mtfftpt(data,tapers,nfft,t,f,findx); % mt fft for point process times 0059 if err(1)==0; 0060 [C,phi]=cohmathelper(J,err); 0061 elseif err(1)==1; 0062 if fscorr==0; 0063 [C,phi,confC,phierr]=cohmathelper(J,err); 0064 else 0065 [C,phi,confC,phierr]=cohmathelper(J,err,Nsp); 0066 end; 0067 elseif err(1)==2; 0068 if fscorr==0; 0069 [C,phi,confC,phierr,Cerr]=cohmathelper(J,err); 0070 else 0071 [C,phi,confC,phierr,Cerr]=cohmathelper(J,err,Nsp); 0072 end; 0073 end