%GETCLASSI Get class index
%
% INDEX = GETCLASSI(A,LABEL)
%
% INPUT
% A Dataset
% LABEL Label used to label the class in A
%
% OUTPUT
% INDEX Index of LABEL in the label list of A
%
% DESCRIPTION
% In some routines like SELDAT and ROC classes should be defined
% by their index in the label list of the dataset. This label list
% can be retrieved by GETLABLIST or CLASSNAMES. GETCLASSI can be used to
% find the index of the label directly.
%
% SEE ALSO (<a href="http://37steps.com/prtools">PRTools Guide</a>)
% DATASETS, SETLABELS, SETLABLIST GETLABLIST, CLASSNAMES