function ratio = dividem ( a, b )

%% DIVIDEM computes the ratio A/B.
%
%  This function is really simply an illustration of how the error()
%  function can be used when an error is detected.
%
  if ( b == 0 )
    error ( 'A/B undefined when B = 0!' )
  end

  ratio = a / b;

  return
end