


Multi-taper derivative time-frequency spectrum - point process times
Usage:
[dS,t,f]=mtdspectgrampt(data,movingwin,tapers,phi,pad,Fs,fpass,trialave)
Input:
Note that all times can be in arbitrary units. But the units have to be
consistent. So, if E is in secs, win, t have to be in secs, and Fs has to
be Hz. If E is in samples, so are win and t, and Fs=1. In case of spike
times, the units have to be consistent with the units of data as well.
data (structure array of spike times for each channel; also accepts 1d array of spike times) -- required
movingwin (in the form [window winstep] i.e length of moving
window and step size.
Note that units here have
to be consistent with
units of Fs
tapers (precalculated tapers from dpss, or in the form [NW K] e.g [3 5]) -- optional. If not
specified, use [NW K]=[3 5]
phi (angle for evaluation of derivative) -- optional.
Default phi=[0,pi/2] giving the time and frequency
derivatives
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 for fft grid used to calculate fft of prolates. 1/Fs is the time between consecutive
points on the grid used for evaluation of the prolates) - 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
trialave (average over trials when 1, don't average when 0) - optional. Default 0
Output:
dS (spectrum in form angle x time x frequency x channels/trials)
t (times)
f (frequencies)

0001 function [dS,t,f]=mtdspecgrampt(data,movingwin,tapers,phi,pad,Fs,fpass,trialave) 0002 % Multi-taper derivative time-frequency spectrum - point process times 0003 % 0004 % Usage: 0005 % 0006 % [dS,t,f]=mtdspectgrampt(data,movingwin,tapers,phi,pad,Fs,fpass,trialave) 0007 % Input: 0008 % Note that all times can be in arbitrary units. But the units have to be 0009 % consistent. So, if E is in secs, win, t have to be in secs, and Fs has to 0010 % be Hz. If E is in samples, so are win and t, and Fs=1. In case of spike 0011 % times, the units have to be consistent with the units of data as well. 0012 % data (structure array of spike times for each channel; also accepts 1d array of spike times) -- required 0013 % movingwin (in the form [window winstep] i.e length of moving 0014 % window and step size. 0015 % Note that units here have 0016 % to be consistent with 0017 % units of Fs 0018 % tapers (precalculated tapers from dpss, or in the form [NW K] e.g [3 5]) -- optional. If not 0019 % specified, use [NW K]=[3 5] 0020 % phi (angle for evaluation of derivative) -- optional. 0021 % Default phi=[0,pi/2] giving the time and frequency 0022 % derivatives 0023 % pad (padding factor for the FFT) - optional. Defaults to 0. 0024 % e.g. For N = 500, if PAD = 0, we pad the FFT 0025 % to 512 points; if PAD = 2, we pad the FFT 0026 % to 2048 points, etc. 0027 % Fs (binning frequency for fft grid used to calculate fft of prolates. 1/Fs is the time between consecutive 0028 % points on the grid used for evaluation of the prolates) - optional. Default 1. 0029 % fpass (frequency band to be used in the calculation in the form 0030 % [fmin fmax])- optional. 0031 % Default all frequencies between 0 and Fs/2 0032 % trialave (average over trials when 1, don't average when 0) - optional. Default 0 0033 % Output: 0034 % dS (spectrum in form angle x time x frequency x channels/trials) 0035 % t (times) 0036 % f (frequencies) 0037 0038 if nargin < 2; error('Need data and window parameters'); end; 0039 if nargin < 3; tapers=[3 5]; end; 0040 if nargin < 4; phi=[0 pi/2];end; 0041 if nargin < 5;pad=0;end; 0042 if nargin < 6; Fs=1; end; 0043 if nargin < 7; fpass=[0 Fs/2]; end; 0044 if nargin < 8; trialave=0; end; 0045 0046 [mintime,maxtime]=minmaxsptimes(data); 0047 tn=[mintime+movingwin(1)/2:movingwin(2):maxtime-movingwin(1)/2]; 0048 Nwin=round(Fs*movingwin(1)); % number of samples in window 0049 Nstep=round(movingwin(2)*Fs); % number of samples to step through 0050 nfft=2^(nextpow2(Nwin)+pad); 0051 [f,findx]=getfgrid(Fs,nfft,fpass); 0052 tapers=dpsschk(tapers,Nwin)/sqrt(Fs); % check tapers 0053 K=size(tapers,2); 0054 nw=length(tn); 0055 0056 for n=1:nw; 0057 t=linspace(tn(n)-movingwin(1)/2,tn(n)+movingwin(1)/2,Nwin); 0058 datawin=extractspdata(data,[t(1) t(end)]); 0059 [ds,f]=mtdspectrumpt(datawin,tapers,phi,pad,Fs,fpass,trialave,t); 0060 dS(n,:,:,:)=ds; 0061 end; 0062 sz=size(ds); 0063 if length(sz)==3; 0064 dS=permute(dS,[2 1 3 4]); 0065 else; 0066 dS=permute(dS,[2 1 3]); 0067 end; 0068 t=tn;