Home > chronux > spectral_analysis > pointbinned > mtspectrumpb.m

# mtspectrumpb

## PURPOSE Multi-taper spectrum - binned point process

## SYNOPSIS function [S,f,R,Serr]=mtspectrumpb(data,params,fscorr)

## DESCRIPTION ``` Multi-taper spectrum - binned point process

Usage:

[S,f,R,Serr]=mtspectrumpb(data,params,fscorr)
Input:
data (in form samples x channels/trials or a single vector) -- required
params: structure with fields tapers, pad, Fs, fpass, err, trialave
- 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.
trialave (average over channels/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:
S       (spectrum in form frequency x channels/trials if trialave=0;
as a function of frequency if trialave=1)
f       (frequencies)
R       (spike rate)
Serr    (error bars) - only for err(1)>=1```

## CROSS-REFERENCE INFORMATION This function calls:
• mtfftpb Multi-taper fourier transform - binned point process data
This function is called by:
• mtspecgrampb Multi-taper time-frequency spectrum - binned point process
• mtspectrumtrigpb Multi-taper event triggered time-frequency spectrum - binned point process

## SOURCE CODE ```0001 function [S,f,R,Serr]=mtspectrumpb(data,params,fscorr)
0002 % Multi-taper spectrum - binned point process
0003 %
0004 % Usage:
0005 %
0006 % [S,f,R,Serr]=mtspectrumpb(data,params,fscorr)
0007 % Input:
0008 %       data (in form samples x channels/trials or a single vector) -- required
0009 %       params: structure with fields tapers, pad, Fs, fpass, err, trialave
0010 %       - optional
0011 %           tapers : precalculated tapers from dpss or in the one of the following
0012 %                    forms:
0013 %                    (1) A numeric vector [TW K] where TW is the
0014 %                        time-bandwidth product and K is the number of
0015 %                        tapers to be used (less than or equal to
0016 %                        2TW-1).
0017 %                    (2) A numeric vector [W T p] where W is the
0018 %                        bandwidth, T is the duration of the data and p
0019 %                        is an integer such that 2TW-p tapers are used. In
0020 %                        this form there is no default i.e. to specify
0021 %                        the bandwidth, you have to specify T and p as
0022 %                        well. Note that the units of W and T have to be
0023 %                        consistent: if W is in Hz, T must be in seconds
0024 %                        and vice versa. Note that these units must also
0025 %                        be consistent with the units of params.Fs: W can
0026 %                        be in Hz if and only if params.Fs is in Hz.
0027 %                        The default is to use form 1 with TW=3 and K=5
0028 %
0029 %            pad            (padding factor for the FFT) - optional (can take values -1,0,1,2...).
0030 %                    -1 corresponds to no padding, 0 corresponds to padding
0031 %                    to the next highest power of 2 etc.
0032 %                       e.g. For N = 500, if PAD = -1, we do not pad; if PAD = 0, we pad the FFT
0033 %                       to 512 points, if pad=1, we pad to 1024 points etc.
0034 %                       Defaults to 0.
0035 %           Fs   (sampling frequency) - optional. Default 1.
0036 %           fpass    (frequency band to be used in the calculation in the form
0037 %                                   [fmin fmax])- optional.
0038 %                                   Default all frequencies between 0 and Fs/2
0039 %           err  (error calculation [1 p] - Theoretical error bars; [2 p] - Jackknife error bars
0040 %                                   [0 p] or 0 - no error bars) - optional. Default 0.
0041 %           trialave (average over channels/trials when 1, don't average when 0) - optional. Default 0
0042 %       fscorr   (finite size corrections, 0 (don't use finite size corrections) or
0043 %                1 (use finite size corrections) - optional
0044 %                (available only for spikes). Defaults 0.
0045 % Output:
0046 %       S       (spectrum in form frequency x channels/trials if trialave=0;
0047 %               as a function of frequency if trialave=1)
0048 %       f       (frequencies)
0049 %       R       (spike rate)
0050 %       Serr    (error bars) - only for err(1)>=1
0051
0052 if nargin < 1; error('Need data'); end;
0053 if nargin < 2; params=[]; end;
0055 clear params
0056 if nargout > 3 && err(1)==0;
0057 %   Cannot compute error bars with err(1)=0. Need to change params and run again
0058     error('When Serr is desired, err(1) has to be non-zero.');
0059 end;
0060 if nargin < 3 || isempty(fscorr); fscorr=0;end;
0061 data=change_row_to_column(data);
0062 N=size(data,1);
0064 [f,findx]=getfgrid(Fs,nfft,fpass);
0065
0066 tapers=dpsschk(tapers,N,Fs); % check tapers
0067 [J,Msp,Nsp]=mtfftpb(data,tapers,nfft);
0068 J=J(findx,:,:);
0069 S=squeeze(mean(conj(J).*J,2));
0070 if trialave; S=squeeze(mean(S,2)); Msp=mean(Msp);end;
0071 R=Msp*Fs;
0072 if nargout==4;
0073    if fscorr==1;
0074       Serr=specerr(S,J,err,trialave,Nsp);
0075    else
0076       Serr=specerr(S,J,err,trialave);
0077    end;
0078 end;```

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