fastica.m

这是一个关于盲源分离独立成分分析方法（ICA）的软件包

  error('Optional parameters should always go by pairs');
else
  for i=1:(nargin-1)/2
    % get the name and value of parameter
    str_param = eval (['s' int2str(i)]);
    val_param = eval (['v' int2str(i)]);

    % change the value of parameter
    if strcmp (str_param, 'verbose')
      verbose = val_param;
      % silence this program also
      if strcmp (verbose, 'off'), b_verbose = 0; end
    elseif strcmp (str_param, 'firstEig')
      firstEig = val_param;
    elseif strcmp (str_param, 'lastEig')
      lastEig = val_param;
    elseif strcmp (str_param, 'interactivePCA')
      interactivePCA = val_param;
    elseif strcmp (str_param, 'approach')
      approach = val_param;
    elseif strcmp (str_param, 'numOfIC')
      numOfIC = val_param;
      % User has suplied new value for numOfIC.
      % We'll use this information later on...
      userNumOfIC = 1;
    elseif strcmp (str_param, 'g')
      g = val_param;
    elseif strcmp (str_param, 'a1')
      a1 = val_param;
    elseif strcmp (str_param, 'a2')
      a2 = val_param;
    elseif strcmp (str_param, 'epsilon')
      epsilon = val_param;
    elseif strcmp (str_param, 'maxNumIterations')
      maxNumIterations = val_param;
    elseif strcmp (str_param, 'initGuess')
      % no use setting 'guess' if the 'initState' is not set
      initState = 'guess';
      guess = val_param;
    elseif strcmp (str_param, 'displayMode')
      displayMode = val_param;
    elseif strcmp (str_param, 'displayInterval')
      displayInterval = val_param;
    elseif strcmp (str_param, 'pcaE')
      % calculate if there are enought parameters to skip PCA
      jumpPCA = jumpPCA + 1;
      E = val_param;
    elseif strcmp (str_param, 'pcaD')
      % calculate if there are enought parameters to skip PCA
      jumpPCA = jumpPCA + 1;
      D = val_param;
    elseif strcmp (str_param, 'whiteSig')
      % calculate if there are enought parameters to skip PCA and whitening
      jumpWhitening = jumpWhitening + 1;
      whitesig = val_param;
    elseif strcmp (str_param, 'whiteMat')
      % calculate if there are enought parameters to skip PCA and whitening
      jumpWhitening = jumpWhitening + 1;
      whiteningMatrix = val_param;
    elseif strcmp (str_param, 'dewhiteMat')
      % calculate if there are enought parameters to skip PCA and whitening
      jumpWhitening = jumpWhitening + 1;
      dewhiteningMatrix = val_param;
    elseif strcmp (str_param, 'only')
      % if the user only wants to calculate PCA or...
      if strcmp(val_param, 'pca')
        only = 1;
      elseif strcmp(val_param, 'white')
        only = 2;
      elseif strcmp(val_param, 'all')
        only = 3;
      end

    else
      % Hmmm, something wrong with the parameter string
      error(['Unrecognized parameter: ''' str_param '''']);
    end;
  end;
end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Check if the data has been entered the wrong way,
% but warn only... it may be on purpose

if Dim > NumOfSampl
  if b_verbose
    fprintf('Warning: ');
    fprintf('The signal matrix may be oriented in the wrong way.\n');
    fprintf('In that case transpose the matrix.\n\n');
  end
end


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Calculating PCA

% We need the results of PCA for whitening, but if we don't
% need to do whitening... then we dont need PCA...
if jumpWhitening == 3
  if b_verbose,
      fprintf ('Whitened signal and corresponding matrises suplied.\n');
      fprintf ('PCA calculations not needed.\n');
    end;
else

  % OK, so first we need to calculate PCA
  % Check to see if we already have the PCA data
  if jumpPCA == 2,
    if b_verbose,
      fprintf ('Values for PCA calculations suplied.\n');
      fprintf ('PCA calculations not needed.\n');
    end;
  else
    % display notice if the user entered one, but not both, of E and D.
    if (jumpPCA > 0) & (b_verbose),
      fprintf ('You must suply all of these in order to jump PCA:\n');
      fprintf ('''pcaE'', ''pcaD''.\n');
    end;

    % Calculate PCA
    [E, D]=pcamat(mixedsig, firstEig, lastEig, interactivePCA, verbose);
  end
end

% skip the rest if user only wanted PCA
if only > 1

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Whitening the data

% Check to see if the whitening is needed...
if jumpWhitening == 3,
  if b_verbose,
    fprintf ('Whitening not needed.\n');
  end;
else

  % Whitening is needed
  % display notice if the user entered some of the whitening info, but not all.
  if (jumpWhitening > 0) & (b_verbose),
    fprintf ('You must suply all of these in order to jump whitening:\n');
    fprintf ('''whiteSig'', ''whiteMat'', ''dewhiteMat''.\n');
  end;

  % Calculate the whitening
  [whitesig, whiteningMatrix, dewhiteningMatrix] = ...
           whitenv (mixedsig, E, D, verbose);
end

end % if only > 1

% skip the rest if user only wanted PCA and whitening
if only > 2

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Calculating the ICA

% Check some parameters
% The dimension of the data may have been reduced during PCA calculations.
% The original dimension is calculated from the data by default, and the
% number of IC is by default set to equal that dimension.

Dim = size(whitesig, 1);

% In symmetric approach the number of IC must equal the dimension of data.
if strcmp (approach, 'symm')
  if numOfIC ~= Dim
    numOfIC = Dim;
    % Show warning only if verbose = 'on' and user suplied a value for 'numOfIC'
    if (b_verbose & userNumOfIC)
      fprintf('Warning: estimating %d independent components\n', numOfIC);
      fprintf('(In symmetric approach we estimate all available independent components)\n');
    end
  end
else
  % In deflation approach the number of IC can be different from the
  % dimension of data, but it must be less or equal.
  if numOfIC > Dim
    numOfIC = Dim;
    % Show warning only if verbose = 'on' and user suplied a value for 'numOfIC'
    if (b_verbose & userNumOfIC)
      fprintf('Warning: estimating only %d independent components\n', numOfIC);
      fprintf('(Can''t estimate more independent components than dimension of data)\n');
    end
  end
end

% Calculate the ICA with fixed point algorithm.
[A, W] = fpica (whitesig,  whiteningMatrix, dewhiteningMatrix, ...
  approach, numOfIC, g, a1, a2, epsilon, maxNumIterations, ...
  initState, guess, displayMode, displayInterval, verbose);


end % if only > 2

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% The output depends on the number of output parameters
% and the 'only' parameter.

if only == 1    % only PCA
  Out1 = E;
  Out2 = D;
elseif only == 2  % only PCA & whitening
  if nargout == 2
    Out1 = whiteningMatrix;
    Out2 = dewhiteningMatrix;
  else
    Out1 = whitesig;
    Out2 = whiteningMatrix;
    Out3 = dewhiteningMatrix;
  end
else      % ICA
  if nargout == 2
    Out1 = A;
    Out2 = W;
  else
    Out1 = W * mixedsig;
    Out2 = A;
    Out3 = W;
  end
end