Home > chronux > spectral_analysis > continuous > mtspecgramtrigc.m

# mtspecgramtrigc

## PURPOSE Multi-taper event triggered time-frequency spectrum - continuous process

## SYNOPSIS function [S,t,f,Serr]=mtspecgramtrigc(data,E,win,movingwin,params)

## DESCRIPTION ``` Multi-taper event triggered time-frequency spectrum - continuous process

Usage:

[S,t,f,Serr]=mtspecgramtrigc(data,E,win,movingwin,params)
Input:
Note units have to be consistent. Thus, if movingwin is in seconds, Fs
data        (single channel data) -- required
E           (event times) -- required
win         (in the form [winl winr] i.e window around each event)
required
movingwin         (in the form [window winstep] i.e length of moving
window and step size) -
required
Note that units for the windows have
to be consistent with
units of Fs
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
Note that T has to be equal to movingwin(1).

pad            (padding factor for the FFT) - optional (can take values -1,0,1,2...).
to the next highest power of 2 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 events when 1, don't average when 0) - optional. Default 0
Output:
S       (triggered spectrum in form time x frequency x events for trialave=0;
or in the form time x frequency trialave=1)
t       (times)
f       (frequencies)
Serr    (error bars) only for err(1)>=1```

## CROSS-REFERENCE INFORMATION This function calls:
• createdatamatc Helper function to create an event triggered matrix from univariate
• mtspecgramc Multi-taper time-frequency spectrum - continuous process
This function is called by:

## SOURCE CODE ```0001 function [S,t,f,Serr]=mtspecgramtrigc(data,E,win,movingwin,params)
0002 % Multi-taper event triggered time-frequency spectrum - continuous process
0003 %
0004 % Usage:
0005 %
0006 % [S,t,f,Serr]=mtspecgramtrigc(data,E,win,movingwin,params)
0007 % Input:
0008 % Note units have to be consistent. Thus, if movingwin is in seconds, Fs
0009 % has to be in Hz. see chronux.m for more information.
0010 %       data        (single channel data) -- required
0011 %       E           (event times) -- required
0012 %       win         (in the form [winl winr] i.e window around each event)
0013 %                                                 required
0014 %       movingwin         (in the form [window winstep] i.e length of moving
0015 %                                                 window and step size) -
0016 %                                                 required
0017 %                                                 Note that units for the windows have
0018 %                                                 to be consistent with
0019 %                                                 units of Fs
0020 %       params: structure with fields tapers, pad, Fs, fpass, err, trialave
0021 %       - optional
0022 %           tapers : precalculated tapers from dpss or in the one of the following
0023 %                    forms:
0024 %                    (1) A numeric vector [TW K] where TW is the
0025 %                        time-bandwidth product and K is the number of
0026 %                        tapers to be used (less than or equal to
0027 %                        2TW-1).
0028 %                    (2) A numeric vector [W T p] where W is the
0029 %                        bandwidth, T is the duration of the data and p
0030 %                        is an integer such that 2TW-p tapers are used. In
0031 %                        this form there is no default i.e. to specify
0032 %                        the bandwidth, you have to specify T and p as
0033 %                        well. Note that the units of W and T have to be
0034 %                        consistent: if W is in Hz, T must be in seconds
0035 %                        and vice versa. Note that these units must also
0036 %                        be consistent with the units of params.Fs: W can
0037 %                        be in Hz if and only if params.Fs is in Hz.
0038 %                        The default is to use form 1 with TW=3 and K=5
0039 %                    Note that T has to be equal to movingwin(1).
0040 %
0041 %            pad            (padding factor for the FFT) - optional (can take values -1,0,1,2...).
0043 %                    to the next highest power of 2 etc.
0044 %                       e.g. For N = 500, if PAD = -1, we do not pad; if PAD = 0, we pad the FFT
0045 %                       to 512 points, if pad=1, we pad to 1024 points etc.
0046 %                       Defaults to 0.
0047 %           Fs   (sampling frequency) - optional. Default 1.
0048 %           fpass    (frequency band to be used in the calculation in the form
0049 %                                   [fmin fmax])- optional.
0050 %                                   Default all frequencies between 0 and Fs/2
0051 %           err  (error calculation [1 p] - Theoretical error bars; [2 p] - Jackknife error bars
0052 %                                   [0 p] or 0 - no error bars) - optional. Default 0.
0053 %           trialave (average over events when 1, don't average when 0) - optional. Default 0
0054 % Output:
0055 %       S       (triggered spectrum in form time x frequency x events for trialave=0;
0056 %               or in the form time x frequency trialave=1)
0057 %       t       (times)
0058 %       f       (frequencies)
0059 %       Serr    (error bars) only for err(1)>=1
0060
0061 if nargin < 4; error('Need data, events and parameters for the windows'); end;
0062 if nargin < 5; params=[]; end;
0063
0064 if length(params.tapers)==3 & movingwin(1)~=params.tapers(2);
0065     error('Duration of data in params.tapers is inconsistent with movingwin(1), modify params.tapers(2) to proceed')
0066 end
0067
0069 clear tapers pad fpass trialave
0070 if nargout > 3 && err(1)==0;
0071 %   Cannot compute error bars with err(1)=0. change params and run again.
0072     error('When Serr is desired, err(1) has to be non-zero.');
0073 end;
0074 data=change_row_to_column(data);
0075 data=createdatamatc(data,E,Fs,win);
0076 if nargout==4;
0077     [S,t,f,Serr]=mtspecgramc(data,movingwin,params);
0078 else
0079     [S,t,f]=mtspecgramc(data,movingwin,params);
0080 end;```

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