Brief IO examples
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Automatic output:
MATLAB will show an expression's value if you do not suppress the output
 
  >> 1 + 1
  ans =
        2

  Steps:
  - MATLAB adds 1 and 1 and stores the result in builtin variable $ans$
  - MATLAB reports the output

  >> x = 1 + 2
  x = 
      3
  
  Steps:
  - MATLAB adds 1 and 2 and stores the result in x
  - MATLAB reports the value of x
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Displaying strings:
+ use the DISP function for displaying an array of strings:

  disp(string) --> output a string
  disp([string1, string2, ...]) --> concatenate the strings and 
                                    output the result
  >> disp(['a ',' b ',' c']);

+ use num2string(number) to convert a number to a string
  (very useful for DISP!)

  >> value = 2;
  >> disp(['The answer is: ',num2str(value)]);
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Getting input:
+ from user, use INPUT:
  value=input('prompt');
  value=input('prompt','s');

  ex) >> value = input('Enter a number: ');
  ex) >> value = input('Enter a string: ','s');
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Example:

% Get initial input from the user:
  value = str2double(input(prompt,'s'));

% Ensure that the input is legal:
  while ~isreal(value)            | ...  % no complex numbers
	isinf(value)              | ...  % no infinite values
	isnan(value)              | ...  % no NaNs
	~isnumeric(value)         | ...  % no non-numerical values
        floor(value)~=ceil(value) | ...  % no decimal/fraction values
        value < -realmax          | ...  % lower bound of integer
	value > realmax                  % upper bound of integer
    
    % Reprompt the user and get revised input:
      disp('That value is not an integer!');
      value = str2double(input(prompt,'s'));        

  end          
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