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Any tips to updating 'for loop' index!

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Hi, I have an issue while writing a code for a similar situation which is making the 'for loop' repeat again if the index variable updated its value within the loop! for instance, I want the 'for loop' for 'y' to repeat if a flag reach!
Any tips or best approach to implement it! Thanks!
check2nd_t=1;
for x=1:10
%some code
for y=1:10
%if abv(x) >= abb(y)
for z=1:10
if abv(x) > abc(z)
%done
break;
end
if y==10 & z==10 & check2nd_t ~=2 %is it && would make any change!?
check2nd_t=2;
y=1; %***my main point, I want the y loop to repaet again***
%some code
end
end
%some code
end
end

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Accepted Answer

Walter Roberson
Walter Roberson on 5 Jan 2020
check2nd_t=1;
for x=1:10
%some code
do_again = true;
while do_again
do_again = false;
for y=1:10
%if abv(x) >= abb(y)
for z=1:10
if abv(x) > abc(z)
%done
break;
end
if y==10 & z==10 & check2nd_t ~=2 %is it && would make any change!?
check2nd_t=2;
do_again = true;
break;
%***my main point, I want the y loop to repaet again***
%some code
end
end
if do_again; break; end
%some code
end
end
end

  1 Comment

mohammadmusleh3
mohammadmusleh3 on 5 Jan 2020
Thank you for highlighting this method, it leads me to fix the code and run smoothly! (I'd think of it!)

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More Answers (1)

per isakson
per isakson on 4 Jan 2020
Edited: per isakson on 5 Jan 2020
The documentation on for says:
Avoid assigning a value to the index variable within the loop statements. The for statement overrides any changes made to index within the loop.
The intention of your loop (from the first version of your question)
for x=1:10
if x==10
x=1;
end
end
may be implemented by
x = 1; % or maybe 0
while x <= 10
if x==10
x=1;
else
x = x + 1;
end
end

  3 Comments

mohammadmusleh3
mohammadmusleh3 on 4 Jan 2020
Thank you!
I really forget about it, I though it's possible to change the index within the loop.
I updated the question to be more precise! if you can give any idea/approach to implement it, I will be grateful.
Image Analyst
Image Analyst on 5 Jan 2020
Which of the 3 for loops do you want to repeat? The x, y, or z loop? You should really be using while's instead of for's.
mohammadmusleh3
mohammadmusleh3 on 5 Jan 2020
I want to repeat the 'y' loop if z and y reach the end.
Yup, I'd used a while loop as well, thanks to Walter Roberson show a code explains it!
Thank you all!

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