How to start again from the previous step?

I want to do something like:

x = input('value of x:');

y = input('value of y:');

 if (x>=y)
    ...

 else
   fprintf('undesirable');
% Then I want to return to the beginning and ask for new x and y inputs. Is there a way to do this? Thank you!

Answer 1

[Amit]

There are for loop and while loop, that can help you do that.

http://www.mathworks.com/help/matlab/ref/for.html

http://www.mathworks.com/help/matlab/ref/while.html

[Larry]

Hi thx for the advice. I just created a for loop. Could you pls have a check, and if possible suggest better alternatives?

 for i = 1:10 
   x = input('value of x:');
   y = input('value of y:');

   if (x>=y)
    ...;
    break
  else
   fprintf('undesirable');
  end
 end

Another problem is that when 'undesirable' happens, inputs are asked again, but everything is lumped into one line like:

undesirablevalue of x:

Is there a way do separate the sentence into two lines?

[Larry]

Maybe add something after 'undesirable' like:

 fprintf('undesirable\enter');

? What would be the correct command?

[Amit]

This code will work. To separate undesirable with the next one, you can use \n operator which is for new line. One problem with this code is that it will loop for only 10 times. If in 10 times, x does not become >= y, then also the code will exit. You want the loop to go on until its not undesirable. I think while loop would be better.

Try something like this:

x = 1;
y = 10;
while (x < y)
  x = input('value of x:');
  y = input('value of y:');
  if (x < y)
    fprintf('undesirable\n');
  end
end

[Larry]

Thank you so much!:D

I was even thinking about using

 for i=1:inf

to solve the issue you raised, but your while loop just avoids it nicely.