MATLAB by rudra pratap

4.3 Language-specific Features
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else
plot (x , ... )
end
% show the phase plot
4.3.5 Interactive input
The commands input , keyboard, menu, and pause can be used inside a script or
function file for interactive user input. Their descriptions follow.
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Input
The command input ( 'string'), used in the previous example, displays the text
in string on the screen and waits for the user to give keyboard input.
Examples:
• n=input ( 'Largest square matrix size ') ; prompts the user to input the
size of the "largest square matrix" and saves the input in n.
• more= input ('More simulations? (Y /N) ' , 's') ; prompts the user to type
Y for YES and N for NO and stores the input as a string in more. Note that
the second argument, 's', of the command directs MATLAB to save the user
input as a string.
This command can be used to write ·user-jTiendly interactive programs in MATLAB.
Keyboard
The command keyboard inside a script or a function file returns control to the
keyboard at the point where the command occurs. The execution of the function
or the script is not terminated. The command window prompt » changes to
k» to show the special status. At this point, you can check variables already
computed, change their values, and issue any valid MATLAB commands. The
control is returned to the function by typing the word return on the special prompt
k» and then pressing the return/enter key.
This command is useful for debugging functions. Sometimes, in long computations,
you may like to check some intermediate results, plot them and see if the
computation is headed in the right direction, and then let the execution continue.
Example:
% EXKEYBRD : a script file for example of keyboard command
A ones (10) % make a 10x10 matrix of 1s
for i=1 :10
disp(i)
% display the value of i
A(:, i) ; i*A ( : 'i) :
end
% replace the ith column of a
if i==5 % when i = 5
keyboard % return the control to keyboard
end