+
−% COHERE estimates the coherence between time-series objects
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−%
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−% DESCRIPTION: COHERE estimates the coherence between the
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−%              time-series objects in the input analysis objects. 
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−%              The estimate is done by taking 
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−%              the ratio of the CPSD between the two inputs, Sxy, divided by 
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−%              the product of the PSDs of the inputs, Sxx and Syy,              
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−%              and is either magnitude-squared: (abs(Sxy))^2 / (Sxx * Syy) 
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−%              or complex value: Sxy / sqrt(Sxx * Syy)
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−%              Here x is the first input, y is the second input
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−%
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−% CALL:        b = cohere(a1,a2,pl)
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−%
+
−% INPUTS:      a1   - input analysis object
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−%              a2   - input analysis object
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−%              pl   - input parameter list
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−%
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−% OUTPUTS:     b    - output analysis object
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−%
+
−% <a href="matlab:utils.helper.displayMethodInfo('ao', 'cohere')">Parameters Description</a>
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−%
+
−% VERSION:    $Id: cohere.m,v 1.43 2011/04/08 08:56:16 hewitson Exp $
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−%
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−
+
−function varargout = cohere(varargin)
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−
+
−  % Check if this is a call for parameters
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−  if utils.helper.isinfocall(varargin{:})
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−    varargout{1} = getInfo(varargin{3});
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−    return
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−  end
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−
+
−  import utils.const.*
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−  utils.helper.msg(msg.PROC3, 'running %s/%s', mfilename('class'), mfilename);
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−
+
−  if nargout == 0
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−    error('### cohere cannot be used as a modifier. Please give an output variable.');
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−  end
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−
+
−  % Collect input variable names
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−  in_names = cell(size(varargin));
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−  for ii = 1:nargin,in_names{ii} = inputname(ii);end
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−
+
−  % Collect all AOs
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−  [as, ao_invars] = utils.helper.collect_objects(varargin(:), 'ao', in_names);
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−
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−  % Apply defaults to plist
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−  pl = applyDefaults(getDefaultPlist, varargin{:});
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−
+
−  % Throw an error if input is not two AOs
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−  if numel(as) ~= 2
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−    error('### cohere only accepts two inputs AOs.');
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−  end
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−  
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−  % Compute coherence with xspec
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−  scale_type = find(pl, 'Type');
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−  switch lower(scale_type)
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−    case 'c'
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−      bs = xspec(as, pl, 'cohere', getInfo, ao_invars);
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−    case 'ms'
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−      bs = xspec(as, pl, 'mscohere', getInfo, ao_invars);
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−    otherwise
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−      error(['### Unknown coherence type: [' scale_type ']']);
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−  end
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−
+
−  % Set output
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−  varargout{1} = bs;
+
−
+
−end
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−
+
−%--------------------------------------------------------------------------
+
−% Get Info Object
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−%--------------------------------------------------------------------------
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−function ii = getInfo(varargin)
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−  if nargin == 1 && strcmpi(varargin{1}, 'None')
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−    sets = {};
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−    pl   = [];
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−  else
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−    sets = {'Default'};
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−    pl   = getDefaultPlist();
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−  end
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−  % Build info object
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−  ii = minfo(mfilename, 'ao', 'ltpda', utils.const.categories.sigproc, '$Id: cohere.m,v 1.43 2011/04/08 08:56:16 hewitson Exp $', sets, pl);
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−  ii.setModifier(false);
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−  ii.setArgsmin(2);
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−end
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−
+
−%--------------------------------------------------------------------------
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−% Get Default Plist
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−%--------------------------------------------------------------------------
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−
+
−function plout = getDefaultPlist()
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−  persistent pl;  
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−  if ~exist('pl', 'var') || isempty(pl)
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−    pl = buildplist();
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−  end
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−  plout = pl;  
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−end
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−
+
−function pl = buildplist()
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−  
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−  % General plist for Welch-based, linearly spaced spectral estimators
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−  pl = plist.WELCH_PLIST;
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−  
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−  % Type
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−  p = param({'Type',['type of output scaling. Choose from:<ul>', ...
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−    '<li>MS - Magnitude-Squared Coherence:<br><tt>(abs(Sxy))^2 / (Sxx * Syy)</tt></li>', ...
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−    '<li>C  - Complex Coherence:<br><tt>Sxy / sqrt(Sxx * Syy)</tt></li></ul>']}, {1, {'C', 'MS'}, paramValue.SINGLE});
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−  pl.append(p);
+
−  
+
−end
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−