gusucode.com > 《精通matlab 7》包括配套光盘 > 配套光盘里的程序附件/Ex-30/testclass/@polynom/subsref.m

    function b = subsref(a,s)
% SUBSREF 
switch s.type
case '()'
    ind = s.subs{:};
    for k = 1:length(ind)
        b(k) = eval(strrep(char(a),'x',num2str(ind(k))));
    end
otherwise
   error('Specify value for x as p(x)')
end