%SELCLASSFixed mapping for selecting a single class from a dataset
%
% [B,J] = SELCLASS(A,CLASS,NAME)
% [B,J] = A*SELCLASS([],CLASS,NAME)
% [B,J] = A*SELCLASS(CLASS,NAME)
%
% INPUT
% A Dataset
% CLASS Integer: Indices of desired classes in CLASSNAMES(A)
% String array: Class names
% Cell array: Indices of desired classes in CLASSNAMES(A)
% Default C = {}, i.e. return all classes separated out in a cell
% array.
% NAME Integer: Index of desired labeling, see GETLABLISTNAMES
% String: Name of desired labeling, see GETLABLISTNAMES
% Default: actual LABLIST
%
% OUTPUT
% B Desired classes of the dataset A. In case CLASS is a cell array, B
% is a cell array of the desired classes. In case CLASS is empty, B
% is a cell array of all classes.
% J Indices of returned objects in dataset A: B = A(J,:). In case CLASS
% is a cell array, J is a cell array as well.
%
% DESCRIPTION
% B is a subset of the dataset A defined by the set of classes (CLASS). In
% case of a multi-labeling system (see MULTI_LABELING) the desired CLASS
% should refer to the label list NAME.
%
% In case A is soft labeled or is a target dataset by B = SELCLASS(A,CLASS)
% the entire dataset is returned, but the labels or targets are reduced to
% the selected class (target) CLASS.
%
% In case CLASS is a cell array the outputs are organised as cell arrays.
%
% EXAMPLES
% a = gendatm; b = selclass(a,[2 3 4]); % selects 3 classes
% a = gendatm; b = a*selclass; % returns every class in a cell
% a = gendatb;
% a = addlabels(a,genlab(25*ones(4,1)),'4class'); % add second label list
% b = a*selclass('4class'); % returns 4 cells, preserves label list.
%
% SEE ALSO (<a href="http://37steps.com/prtools">PRTools Guide</a>)
% DATASETS, SELDAT, CLASSNAMES, GENDAT, GETLABLIST, GETCLASSI, REMCLASS,
% GETLABLISTNAMES, MULTI_LABELING
% Copyright: R.P.W. Duin, r.p.w.duin@37steps.com
function [b,J] = selclass(varargin)
argin = shiftargin(varargin,{'vector','cell','char'});
argin = shiftargin(argin,'char',2);
argin = setdefaults(argin,[],{},[]);
if mapping_task(argin,'definition')
b = define_mapping(argin,'fixed');
else % Evaluate
[a,clas,lablist] = deal(argin{:});
isa(a,'prdataset');
if ~isempty(lablist)
curn = curlablist(a);
a = changelablist(a,lablist);
[b,J] = feval(mfilename,a,clas);
if iscell(b)
for n=1:numel(b)
b{n} = changelablist(b{n},curn);
end
else
b = changelablist(b,curn);
end
else
if iscell(clas)
if isempty(clas)
for n=1:getsize(a,3);
clas{n} = n;
end
end
if isdataset(a)
b = prdataset;
else
b = prdatafile;
end
J = cell(1,numel(clas));
b = cell(1,numel(clas));
for n=1:numel(clas)
[b{n},J{n}] = seldat(a,clas{n});
end
else
[b,J] = seldat(a,clas);
end
end
end