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    %% Controlling Number Display While Rounding  

%% 
% The |format| command controls how MATLAB(R) displays numbers at the
% command line. If a number has extra digits that cannot be displayed in
% the current format, then MATLAB automatically rounds the number for
% display purposes. This can lead to unexpected results when combined with
% the |round| function.
%
% Consider the result of the following subtraction operation, which
% displays 5 digits.
format short
x = 112.05 - 110  

%% 
% Based on the displayed value of |x|, rounding |x| to 1 decimal should
% return |2.1|. 
round(x,1)  

%% 
% In fact, the problem here is that MATLAB is rounding |x| to 5 digits for
% display purposes. The |round| function returns the correct answer.
% Confirm the answer by viewing |x| with |format long|, which displays |x|
% rounded to 15 digits.
format long
x