%UNIT Unitize a vector
%
% VN = UNIT(V) is a unit vector parallel to V.
%
% Note::
% - Reports error for the case where norm(V) is zero.


% Copyright (C) 1993-2011, by Peter I. Corke
%
% This file is part of The Robotics Toolbox for Matlab (RTB).
% 
% RTB is free software: you can redistribute it and/or modify
% it under the terms of the GNU Lesser General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
% 
% RTB is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU Lesser General Public License for more details.
% 
% You should have received a copy of the GNU Leser General Public License
% along with RTB.  If not, see <http://www.gnu.org/licenses/>.

function u = unit(v)
    n = norm(v, 'fro');
    if n < eps
        error('RTB:unit:zero_norm', 'vector has zero norm');
    end

	u = v / n;