glm_rfx_removepredictors.m

toolbox of BVQX, This is the access between BV and matlab. It will help you to analysis data from BV

function hfile = glm_RFX_RemovePredictors(hfile, removep)
% GLM::RFX_RemovePredictors  - removes predictors for each subject
%
% FORMAT:       [glm] = glm.RFX_RemovePredictors(removep)
%
% Input fields:
%
%       removep     specification of predictors to remove

% Version:  v0.7b
% Build:    7083023
% Date:     Aug-30 2007, 11:21 PM CEST
% Author:   Jochen Weber, Brain Innovation, B.V., Maastricht, NL
% URL/Info: http://wiki.brainvoyager.com/BVQXtools

% argument check
if nargin < 2 || ...
    numel(hfile) ~= 1 || ...
   ~isBVQXfile(hfile, 'glm') || ...
   ~isa(removep, 'double') || ...
    isempty(removep) || ...
    any(isinf(removep(:)) | isnan(removep(:)) | removep(:) < 1 | ...
        removep(:) ~= fix(removep(:)))
    error( ...
        'BVQXfile:BadArgument', ...
        'Invalid call to %s.', ...
        mfilename ...
    );
end
bc = bvqxfile_getcont(hfile.L);
if bc.ProjectTypeRFX ~= 1 || ...
    any(removep(:) > bc.NrOfSubjectPredictors)
    error( ...
        'BVQXfile:BadArgument', ...
        'Invalid call to %s.', ...
        mfilename ...
    );
end

% get needed numbers
removep = removep(:)';
nums = bc.NrOfSubjects;
nump = bc.NrOfSubjectPredictors;

% build to-be-removed/-kept index variables
remi = false(1, nump);
remi(removep) = true;
keepi = ~remi;
remi = repmat(remi, [1, nums]);
nnump = sum(~remi) / nums;
if nnump ~= fix(nnump)
    error( ...
        'BVQXfile:InvalidObject', ...
        'Invalid object given.' ...
    );
end

% make changes
bc.NrOfSubjectPredictors = nnump;
bc.NrOfPredictors = sum(~remi);
bc.Predictor(remi) = [];

% alter BetaMaps
switch (bc.ProjectType)
    case {0, 1}
        for sc = 1:nums
            bc.GLMData.Subject(sc).BetaMaps = ...
                bc.GLMData.Subject(sc).BetaMaps(:, :, :, keepi);
        end
    case {2}
        for sc = 1:nums
            bc.GLMData.Subject(sc).BetaMaps = ...
                bc.GLMData.Subject(sc).BetaMaps(:, keepi);
        end
    otherwise
        error( ...
            'BVQXfile:InvalidObject', ...
            'Invalid ProjectType setting in GLM.' ...
        );
end

% set back
bvqxfile_setcont(hfile.L, bc);