How do I exit a for loop after logical index is found true in an array?

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Struggling in MATLAB 2022-12-4

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https://ww2.mathworks.cn/matlabcentral/answers/1870527-how-do-i-exit-a-for-loop-after-logical-index-is-found-true-in-an-array

评论： Struggling in MATLAB 2022-12-4

I would like to exit a loop if the result is set to true in the for loop. But it always returns false if I use 'continue'. How do I resolve this?

% check if trajectory goes through the zone
result = false;
for i = 1:length(xNormalized)
    if (xNormalized(i) > xEdge(1) && xNormalized(i) < xEdge(2)) && ...
        (yNormalized(i) > yEdge(1) && yNormalized(i) < yEdge(2))
        result = true;
    end
    % continue;
end

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Answer 1

VBBV 2022-12-4

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use inside the if-end statement

% check if trajectory goes through the zone
result = false;
for i = 1:length(xNormalized)
    if (xNormalized(i) > xEdge(1) && xNormalized(i) < xEdge(2)) && ...
        (yNormalized(i) > yEdge(1) && yNormalized(i) < yEdge(2))
        result = true
        break  % use inside the if - condition
    end
     
end

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VBBV 2022-12-4

编辑：VBBV 2022-12-4

If you use outside the if condition the result state may not be saved to true if this for loop is nested inside another loop which means it will restore the result state back to false. I presume, this for loop is present inside another loop, thats why result flag is being set to false again.

If you want to avoid reuslt to set false, you need to place the result flag outside of all nested loops.

Struggling in MATLAB 2022-12-4

Thank you! I was using outside the if statement and that did not work. It works if I use inside if as you suggested. By the way, this for loop is the outermost loop.

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