Matlab 2021b: Run Section now interrupts currently running section?

I have recently upgraded to MATLAB 2021b. In my script, I often run one section of my code (Command+Enter), and "queue up" another section of my code to run by clicking to that section and running that section with the same hotkey. This is helpful when debugging, for example, and I want to only run only some nonsequential sections of the script.

In MATLAB 2020a, this worked without a problem: the first section would run, then the second section. Now however, when I do this same thing, the first section of code will be interrupted with the error:

Operation terminated by user during LiveEditorEvaluationHelperE2113566987 (line 8)

How can this be fixed or changed? I have looked through the Preferences and found nothing relevant.

[Chaona Chen]

I have this issue as well after install 2021b. It is really annoying.

[Joseph Williams]

Chaona, I am glad at least that someone else is experiencing this issue, not just me. It is such a bizarre bug.

Answer 1

[Michael Zauner]

it seems Matlab has changed the way 'Run section' works in the 2021b release.

The 'Run section' now queues the next execution instead of instantly triggering it.

See: https://de.mathworks.com/matlabcentral/answers/1568788-matlab-2021b-run-section-in-debugging-mode-not-working-anymore

[Joseph Williams]

Thanks for bringing visibility to this topic with your response and your insightful post.

Answer 2

[Srijith Kasaragod]

Hi Joseph,

This is a known issue which the developers are already aware of and might be fixed in a future release.

A workaround could be to use "Run and Advance" ("Ctrl+Shift+Enter") instead of "Run Section", upon which none of the sections get terminated.

Hope this helps!

[Bram]

It might be fixed in a future release?

Answer 3

[Joseph Williams]

To provide some further details, this bug appears irrespective of the code being executed. For example, it is easy to recreate this bug with the following code. First, run only the first code section, then run the second code section while the first is still executing.

%% First code section

for i = 1:2:10
    fprintf('i = %d\n',i)
    pause(0.5)
end

%% Second code section

for j = 2:2:10
    fprintf('j = %d\n',j)
    pause(0.5)
end