function [S,f,R,varS,zerosp,C,Serr]=mtspectrumsegpb(data,win,params,segave,fscorr)
% Multi-taper segmented spectrum for a univariate binned point process
%
% Usage:
%
% [S,f,R,varS,zerosp,C,Serr]=mtspectrumsegpb(data,win,params,segave,fscorr)
% Input:
% Note units have to be consistent. See chronux.m for more information.
% data (single vector) -- required
% win (duration of the segments) - required.
% params: structure with fields tapers, pad, Fs, fpass, err
% - optional
% tapers : precalculated tapers from dpss or in the one of the following
% forms:
% (1) A numeric vector [TW K] where TW is the
% time-bandwidth product and K is the number of
% tapers to be used (less than or equal to
% 2TW-1).
% (2) A numeric vector [W T p] where W is the
% bandwidth, T is the duration of the data and p
% is an integer such that 2TW-p tapers are used. In
% this form there is no default i.e. to specify
% the bandwidth, you have to specify T and p as
% well. Note that the units of W and T have to be
% consistent: if W is in Hz, T must be in seconds
% and vice versa. Note that these units must also
% be consistent with the units of params.Fs: W can
% be in Hz if and only if params.Fs is in Hz.
% The default is to use form 1 with TW=3 and K=5
%
% pad (padding factor for the FFT) - optional (can take values -1,0,1,2...).
% -1 corresponds to no padding, 0 corresponds to padding
% to the next highest power of 2 etc.
% e.g. For N = 500, if PAD = -1, we do not pad; if PAD = 0, we pad the FFT
% to 512 points, if pad=1, we pad to 1024 points etc.
% Defaults to 0.
% 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.
% segave (1 for averaging across segments, 0 otherwise; default 1)
% 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:
% S (spectrum in form frequency x segments if segave=0; as a function of frequency if segave=1)
% f (frequencies)
% R (spike rate)
% varS (variance of the log spectrum)
% zerosp (0 for segments in which spikes were found, 1 for segments
% in which there are no spikes)
% C (covariance matrix of the log spectrum - frequency x
% frequency matrix)
% Serr (error bars) - only for err(1)>=1
if nargin < 2; error('Need data and segment information'); end;
if nargin < 3; params=[]; end;
if nargin < 4 || isempty(segave); segave=1; end;
[tapers,pad,Fs,fpass,err,trialave,params]=getparams(params);
clear params trialave
if nargin < 3 || isempty(fscorr); fscorr=0;end;
if nargout > 4 && err(1)==0;
% Cannot compute error bars with err(1)=0. Need to change params and run again.
error('When Serr is desired, err(1) has to be non-zero.');
end;
data=change_row_to_column(data);
N=size(data,1); % total length of data
dt=1/Fs; % sampling interval
T=N*dt; % length of data in seconds
E=0:win:T-win; % fictitious event triggers
win=[0 win]; % use window length to define left and right limits of windows around triggers
data=createdatamatpb(data,E,Fs,win);
N=size(data,1); % length of segmented data
nfft=max(2^(nextpow2(N)+pad),N);
[f,findx]=getfgrid(Fs,nfft,fpass);
tapers=dpsschk(tapers,N,Fs); % check tapers
[J,Msp,Nsp]=mtfftpb(data,tapers,nfft);
J=J(findx,:,:);
R=Msp*Fs;
S=squeeze(mean(conj(J).*J,2)); % spectra of non-overlapping segments (averaged over tapers)
if segave==1; SS=squeeze(mean(S,2));R=mean(R);else;SS=S;end;% mean of the spectrum averaged across segments
if nargout > 3
lS=log(SS); % log spectrum for nonoverlapping segments
% varS=var(lS,1,2); % variance of log spectrum
varS=var(lS',1)';% variance of the log spectrum R13
if nargout > 4
zerosp=zeros(1,size(data,2));
zerosp(Nsp==0)=1;
if nargout > 5
C=cov(lS'); % covariance matrix of the log spectrum
if nargout==7;
if fscorr==1;
Serr=specerr(SS,J,err,segave,Nsp);
else
Serr=specerr(SS,J,err,segave);
end;
end;
end;
end;
end;
S=SS;