function isit = istriangle2(sides)
% istriangle(sides) - check if array of 
%              'sides' is a valid triangle
%
% INPUTS
%   sides : array of 3 numbers
% OUTPUTS
%   isit  : = 1 if valid, = 0 if not valid
 
% find longest side
ii = sides == max(sides);
 
% test it
isit = sides(ii) <= sum(sides(~ii));