Stop for loop if F <= 0

I wonder how it is possible to stop a for loop without using break. I have tried to expand the code with a while loop, but I do not manage to get it to work. Appreciate hints.

n = 20;         
terskelverdi = 0.1;
F = zeros(1,n); 
F(1) = 1;
F(2) = 1;
for k = 3:n 
   r = rand(1); 
   if r > terskelverdi
    F(k) = F(k-1) + F(k-2);  
   else
    F(k) = F(k-1) - F(k-2); 
   end
 end
disp(F)
figure, plot(F,'g-'), grid
title('Fibonaccitall med tilfeldigheter opp til "n"')

[Mohammad Abouali]

just curious, Why you don't want to use break?

Answer 1

[Walter Roberson]

To stop a "for" loop without using "break", you can do one of:

• reach the natural end of iterations for the loop
• "return" to a calling routine
• "error" out to an enclosing try/catch (or the command line)
• quit or exit MATLAB

Answer 2

[Jon]

Why are you opposed to using break? If you mean that you want to redraw a random number if F <=0, you could do something like this:

count = 3;
while 1
     r = rand(1); 
     if r > terskelverdi
      F(count) = F(count-1) + F(count-2);  
     else
      F(count) = F(count-1) - F(count-2); 
     end

     if F(k) > 0
         count = count + 1;
     end

     if count == n
         break
     end
end

but this could cause an infinite loop. Not sure what your objective is, so I can't help more.