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ltpda_cpsd

PURPOSE ^

LTPDA_CPSD makes cross-spectral density estimates of the time-series objects.

SYNOPSIS ^

function varargout = ltpda_cpsd(varargin)

DESCRIPTION ^

 LTPDA_CPSD makes cross-spectral density estimates of the time-series objects.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

 DESCRIPTION: LTPDA_CPSD makes cross-spectral density estimates of the
              time-series objects in the input analysis objects. CPSDs are computed
              using MATLAB's cpsd (>> help cpsd).

 CALL:        b = ltpda_cpsd(a1,a2,a3,...,pl)

 INPUTS:      b    - output analysis objects
              aN   - input analysis objects (at least two)
              pl   - input parameter list

              The function makes CPSD estimates between all input AOs.
              Therefore, if the input argument list contains N analysis objects, the
              output a will contain NxN CPSD estimates. 
              The diagonal elements will be S_ai_ai and will be equivalent to
              the output of ltpda_pwelch(ai)

              If the last input argument is a parameter list (plist) it is used. The
              following parameters are recognised.

 PARAMETERS: 'Win'   - a specwin window object [default: Kaiser -200dB psll]
             'Olap'  - segment percent overlap [default: taken from window function]
             'Nfft'  - number of samples in each fft [default: length of input data]
             'Order' - order of segment detrending:
                        -1 - no detrending
                         0 - subtract mean [default]
                         1 - subtract linear fit
                         N - subtract fit of polynomial, order N  

 VERSION:     $Id: ltpda_cpsd.m,v 1.10 2008/03/30 23:33:26 mauro Exp $

 HISTORY:     07-02-2007 M Hewitson
                 Creation

 The following call returns a parameter list object that contains the
 default parameter values:

 >> pl = ltpda_cpsd('Params')

 The following call returns a string that contains the routine CVS version:

 >> ver = ltpda_cpsd('Version')

 The following call returns a string that contains the routine category:

 >> category = ltpda_cpsd('Category')

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:

SUBFUNCTIONS ^

SOURCE CODE ^

0001 function varargout = ltpda_cpsd(varargin)
0002 % LTPDA_CPSD makes cross-spectral density estimates of the time-series objects.
0003 %
0004 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0005 %
0006 % DESCRIPTION: LTPDA_CPSD makes cross-spectral density estimates of the
0007 %              time-series objects in the input analysis objects. CPSDs are computed
0008 %              using MATLAB's cpsd (>> help cpsd).
0009 %
0010 % CALL:        b = ltpda_cpsd(a1,a2,a3,...,pl)
0011 %
0012 % INPUTS:      b    - output analysis objects
0013 %              aN   - input analysis objects (at least two)
0014 %              pl   - input parameter list
0015 %
0016 %              The function makes CPSD estimates between all input AOs.
0017 %              Therefore, if the input argument list contains N analysis objects, the
0018 %              output a will contain NxN CPSD estimates.
0019 %              The diagonal elements will be S_ai_ai and will be equivalent to
0020 %              the output of ltpda_pwelch(ai)
0021 %
0022 %              If the last input argument is a parameter list (plist) it is used. The
0023 %              following parameters are recognised.
0024 %
0025 % PARAMETERS: 'Win'   - a specwin window object [default: Kaiser -200dB psll]
0026 %             'Olap'  - segment percent overlap [default: taken from window function]
0027 %             'Nfft'  - number of samples in each fft [default: length of input data]
0028 %             'Order' - order of segment detrending:
0029 %                        -1 - no detrending
0030 %                         0 - subtract mean [default]
0031 %                         1 - subtract linear fit
0032 %                         N - subtract fit of polynomial, order N
0033 %
0034 % VERSION:     $Id: ltpda_cpsd.m,v 1.10 2008/03/30 23:33:26 mauro Exp $
0035 %
0036 % HISTORY:     07-02-2007 M Hewitson
0037 %                 Creation
0038 %
0039 % The following call returns a parameter list object that contains the
0040 % default parameter values:
0041 %
0042 % >> pl = ltpda_cpsd('Params')
0043 %
0044 % The following call returns a string that contains the routine CVS version:
0045 %
0046 % >> ver = ltpda_cpsd('Version')
0047 %
0048 % The following call returns a string that contains the routine category:
0049 %
0050 % >> category = ltpda_cpsd('Category')
0051 %
0052 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0053 
0054 %             'Debug' - debug level for terminal output (0-1)
0055 
0056 ALGONAME = mfilename;
0057 VERSION  = '$Id: ltpda_cpsd.m,v 1.10 2008/03/30 23:33:26 mauro Exp $';
0058 CATEGORY = 'Signal Processing';
0059 
0060 
0061 %% Check if this is a call for parameters, the CVS version string
0062 % or the function category
0063 if nargin == 1 && ischar(varargin{1})
0064   in = char(varargin{1});
0065   if strcmp(in, 'Params')
0066     varargout{1} = getDefaultPL();
0067     return
0068   elseif strcmp(in, 'Version')
0069     varargout{1} = VERSION;
0070     return
0071   elseif strcmp(in, 'Category')
0072     varargout{1} = CATEGORY;
0073     return
0074   end
0075 end
0076 
0077 % capture input variable names
0078 invars = {};
0079 as     = [];
0080 ps     = [];
0081 for j=1:nargin
0082   invars = [invars cellstr(inputname(j))];
0083   if isa(varargin{j}, 'ao')
0084     as = [as varargin{j}];
0085   end
0086   if isa(varargin{j}, 'plist')
0087     ps = [ps varargin{j}];
0088   end
0089 end
0090 
0091 
0092 % check plist
0093 if isempty(ps)
0094   pl = getDefaultPL();
0095 else
0096   pl = combine(ps, getDefaultPL);
0097 end
0098 
0099 varargout{1} = ltpda_xspec(as, pl, 'CPSD', ALGONAME, VERSION, invars);
0100 
0101 
0102 %--------------------------------------------------------------------------
0103 % Get default params
0104 function plo = getDefaultPL()
0105 
0106 disp('* creating default plist...');
0107 
0108 plo = plist('Nfft', -0.5, ...
0109   'Win', specwin('Kaiser', 1, 100), ...
0110   'Olap', -1, ...
0111   'Order', 0);
0112 
0113 disp('* done.');
0114 
0115

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