mfbox_pca_run.m

toolbox for spm 5 for data, model free analysis

function [params,A,W,S]=mfbox_PCA_run(X,mask,params,runflag)
% run PCA
%
% Usage:
%  [params,A,W,S]=mfbox_pca_run(X,mask,params,runflag)
%
%  X       - (NxT) data
%  mask    - data mask (XxYxZ) with sum(mask(:))==N
%  params  - struct with
%            numComponents - number of components
%  runflag - -1 get default parameter
%             0 interactive ask parameters
%             1 interactive ask parameters and run
%             2 run
%
% Copyright by Peter Gruber, Ingo R. Keck and Fabian J. Theis
% Computational Intelligence and Machine Learning Group
% Institute of Biophysics, University of Regensburg, Germany
% Homepage: http://mfbox.sourceforge.net
%           http://www-aglang.uni-regensburg.de
%
% This file is free software, subject to the 
% GNU GENERAL PUBLIC LICENSE, see gpl.txt

error(nargchk(1,4,nargin));
error(nargchk(1,4,nargout));

A = [];
W = [];
S = [];

s = size(X);
dim = s(1:(end-1));
if (length(dim)==1), dim = [dim,1]; end
n = s(end);

if (nargin<2), mask = logical(ones(dim)); end
if (nargin<3), params = []; end
if (nargin<4), runflag = 1; end

params = mfbox_checkparam(params,'mf','pca', ...
    struct('numComponents',10,'numComponents_min',1, ...
    'numComponents_max',20,'numComponents_type','int'));

if (abs(runflag-0.5)<1)
    if (exist('OCTAVE_HOME')~=5)% matlab
        params = mfbox_pcag(X,mask,params,runflag);
    elseif (exist('OCTAVE_HOME')==5) %octave
        [params,runflag] = mfbox_getparam(params,runflag);
    end
end

if (runflag>0 && isstruct(params))
    [A,S] = mfbox_pca(X,params.numComponents);
    if (nargout>2), W = pinv(A); end
end