Why does a for-loop stop at the correct place when you use the same counter name as your upper limit?

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Why does this code work, and display the numbers 1-7, rather than stopping at r=1 or going on infinitely (for each step, r=r and the loop continues)?
r=7;
for r=1:r
disp(r)
end

Answers (1)

Ahmet Cecen
Ahmet Cecen on 24 Apr 2018
Because the upper limit is evaluated at the beginning of the execution when r = 7. If you want the loop condition to be evaluated every time the loop iterates, you need to use a while loop. See even if you did something like this:
r=7;
for r=1:r
r=5;
disp(r)
end
You would still get 7 iterations. However now we are overwriting the iterator so you would only get 5s.

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