%GENLAB Generate labels for classes
%
% LABELS = GENLAB(N,LABLIST)
%
% INPUT
% N Number of labels to be generated
% LABLIST Label names (optional; default: numeric labels 1,2,3,...)
%
% OUTPUT
% LABELS Labels in a column vector or strinag array
%
% DESCRIPTION
% Generate a set of labels as defined by the LABLIST. N is a number or
% a row/column vector of the values for each class. If N is a vector, then
% the first N(i) labels get the value LABLIST(i,:). N should have as many
% components as LABLIST. If N is a scalar, then N labels are generated for
% each class. LABLIST is a column vector or a string array. Labels can be
% used to construct a labeled dataset.
%
% EXAMPLES
% Numeric labels, 1..10, 10 classes, 100 labels per class.
% LAB1 = GENLAB(100*ones(1,10));
% Character labels, 3 classes, 10 labels per class.
% LAB2 = GENLAB([10 10 10], ['A';'B';'C']);
% Name labels, 2 classes, 50 labels per class.
% The commands below are equivalent.
% LAB3 = GENLAB([50 50], {'Apple'; 'Pear'});
% LAB3 = GENLAB([50 50], ['Apple'; 'Pear ']);
%
% SEE ALSO (<a href="http://37steps.com/prtools">PRTools Guide</a>)
% DATASETS, DATASET
% Copyright: R.P.W. Duin, duin@ph.tn.tudelft.nl
% Faculty of Applied Sciences, Delft University of Technology
% P.O. Box 5046, 2600 GA Delft, The Netherlands
% $Id: genlab.m,v 1.4 2009/09/23 08:33:55 duin Exp $
function labels = genlab(n,lablist)
if (nargin == 1)
% Create numeric labels.
labels = [];
lab = 1;
if (all(n == n(1))) % All label categories have equal cardinalities.
J = repmat([1:length(n)],n(1),1);
labels = J(:);
else
for i = 1:length(n)
labels = [labels; repmat(lab,n(i),1)];
lab = lab+1;
end
end
labels = int2str(labels);
else % LABLIST present
% Create string or character labels.
if iscell(lablist), lablist = lablist(:); end
[m,ncol] = size(lablist);
if m ~= length(n)
% This is only possible when all label categories have equal cardinalities.
if (length(n) > 1)
error('Wrong number of labels supplied.')
else
J = repmat([1:m],n,1);
labels = lablist(J(:),:);
end
elseif (iscell(lablist)) % Cell array
% We are here when e.g. GENLAB([10 10],{'Apple'; 'Pear'}) is called.
labels = {};
for i = 1:length(n)
labels = [labels; repmat(lablist(i),n(i),1)];
end
labels = char(labels); % cell string labels are not supported anymore
elseif (isstr(lablist)) % Character array
% We are here when e.g. GENLAB([10 10],['Apple'; 'Pear ']) is called.
labels = char(repmat(lablist(1,:),n(1),1));
for i = 2:length(n)
if (n(i) > 0)
labels = char(labels,repmat(lablist(i,:),n(i),1));
end
end
if (n(1) == 0) % First label category not wanted.
labels(1,:) = [];
end
else
% Again numeric labels.
% We are here, when e.g. GENLAB([10 10 10], [3;6;7]) is called.
if (ncol > 1)
error('Labels should be characters, strings or single numbers.')
end
labels = [];
for i = 1:length(n)
labels = [labels; repmat(lablist(i),n(i),1)];
end
end
end
return