Start script at a chosen line

As we know it is not possible to modify a running script. You have to stop the script and restart it for the changes to become active. Now I wonder if it is possible to jump into a script at a chosen line. So one could stop a running process, make the desired changes and then have the program continue in the modified version without running the code before the changed part again.

[Rik]

You can either temporarily comment out all previous code, or run the rest of the code as a section.

[Adam]

Turn it into functions instead. You can edit any function that isn't currently being executed, whether it is called before or after the currently executing code or not.

[Alexander. Koutsouris]

Start you script with:

i=0;

if i==0

else

And set the "end" at the point where you want to run the script

[Rik]

@Alexander, that will have the same effect as commenting out code. It would also make more sense to me if you use this instead:

if false
    %code that shouldn't run
end
%code that should run

That way you don't interfere with any variable that might be used in the rest of the code.

Answer 1

[Jan]

Using a method to stop and re-enter scripts at arbitrary lines would be a meta-interpreter, which runs on top of Matlab. Such a method would be prone to errors and it will be hard to reproduce the results reliably. If you want to run a code with some modifications, create a function and trigger the different methods by using a switch, e.g. controlled by an input argument.

Using structured code and functions is such a great improvement and much more stable than running scripts in dynamically modified pieces, that I cannot imagine, why somebody wants to do it the hard and complicated way.

[Ali Komai]

You are surely right and of course it is better to have the code structured but it is a reoccurring issue for me while debugging. And it is in nature of bugs that they pop up at unforeseen locations in the code. :-) However I got my answer. Thank you!

@Adam: Thank you for pointing this out! I was not aware that editing a function that is not executed at the moment was possible. This will help!

@Rik Wisselink: Thank you for this suggestion. I had the same idea but was wondering if there is another possibility.