source: prextra/removeilab.m @ 100

%REMOVEILAB remove named identifier columns
%
%   B=REMOVEILAB(A,REF)
%
% INPUT
%    A     input dataset with ilab structure (see MAKEILAB)
%    REF   name, cell array with names or numerical indices of
%          identifier columns
% OUTPUT
%    B     output dataset
%
% DESCRIPTION 
% This cunction removes named identifiers (both names and per-example
% values) from a ilab-enabled dataset (see ENABLEILAB).  If no identifier
% name or index is given (REF is empty), the named-identifier capability is
% removed from the dataset.
%
% SEE ALSO
% ENABLEILAB, REMOVEILAB, GETILAB, SETILAB, GETILABLIST

% $Id: removeilab.m,v 1.2 2005/05/02 13:05:46 pavel Exp $

function a=removeilab(a,ref)
    
    isvalidilab(a);

    if ~exist('ref','var')
        u=a.user;
        u=rmfield(u,'ilab');
        a.user=u;
        prwarning(1,'ilab capability was removed from a dataset');
        return
    end
    
    u=a.user;
    
    % get the columns to be set
    col=[];
    if isnumeric(ref)
        col=ref;    
    else
        if ischar(ref)
            ref={ref}; % turn it into cell array
        end
        if ~iscell(ref)
            error('numerical index, name or cell array of names expected')
        end
        % we know ref is a cell array
        for i=1:length(ref)
            ind=strcmp(a.user.ilab.names,ref{i});
            if sum(ind)==0
                error(['identifier label ''' ref{i} ''' not defined!']); 
            end
            col=[col find(ind==1)];
        end
    end
    
    if max(col)>size(a.user.ilab.names,2)
        error('index exceeds number of defined ident labels');
    end

    names=u.ilab.names;
    ncol=sort(setdiff(1:length(a.user.ilab.names),col));
    names=names(ncol);
    u.ilab.names=names;
    a.user=u;
    
    % update ident
    ident=a.ident;
    ident(:,col)=[];
    a.ident=ident;
    
    return