123456789101112131415161718192021222324252627282930 |
- function [J,Msp,Nsp]=mtfftpb(data,tapers,nfft)
- % Multi-taper fourier transform - binned point process data
- %
- % Usage:
- %
- % [J,Msp,Nsp]=mtfftpb(data,tapers,nfft) - all arguments required
- % Input:
- % data (in form samples x channels/trials or single vector)
- % tapers (precalculated tapers from dpss)
- % nfft (length of padded data)
- % Output:
- % J (fft in form frequency index x taper index x channels/trials)
- % Msp (number of spikes per sample in each channel)
- % Nsp (number of spikes in each channel)
- if nargin < 3; error('Need all input arguments'); end;
- data=change_row_to_column(data); % changes data stored as a row vector to a column vector
- [N,C]=size(data); % size of data
- K=size(tapers,2); % size of tapers
- tapers=tapers(:,:,ones(1,C)); % add channel indices to tapers
- H=fft(tapers,nfft,1); % fourier transform of the tapers
- Nsp=sum(data,1); % number of spikes in each channel
- Msp=Nsp'./N; % mean rate for each channel
- meansp=Msp(:,ones(1,K),ones(1,size(H,1))); % add taper and frequency indices to meansp
- meansp=permute(meansp,[3,2,1]); % permute to get meansp with the same dimensions as H
- data=data(:,:,ones(1,K));% add taper indices to the data
- data=permute(data,[1 3 2]); % permute data to be of the same dimensions as H
- data_proj=data.*tapers; % multiply data by the tapers
- J=fft(data_proj,nfft,1); % fft of projected data
- J=J-H.*meansp; % subtract the dc
|