Get signal lines in a linked library in Simulink

[Simulink version 2019b]

I have a Simulink model called 'main.slx' with several linked library blocks (all resolved). One of these ilinked libraries is called 'link1'. I need to get all the signal lines inside 'link1'

Scenario 1:

I open link1.slx directly in Simulink and click on it. I get all the signals using find_system(gcb, 'FindAll', 'on', 'type', 'line'). This works well.

Scenario 2:

I open main.slx in Simulink and click on the link1 block. This time the same find_system command returns empty. I go deeper into link1 and try again, but still no result.

Is there a direct way to achieve this result? Do I need to get the pathname for link1, open it locally and then run the find_system command? That would be very time-consuming. Hopefully there's a better/faster way? TIA.

Answer 1

[Fangjun Jiang]

Not sure if "link1.slx" is a model/subsystem or a library, which results in a subsystem reference or a library link.

In any case, it sounds like you need to add one of these options

'FollowLinks','On'

'LookInsideSubsystemReference','On'

[Prabhakar Vallury]

Definitely a linked library, Jiant. I tried all combinations, but it didn't work. I finally made some workarounds to check if it had a referenced library block (using 'LinkStatus') and built some logic around that. Not ideal, but gets the work done.

However, now I have a different but related problem.

In a model containing linked library blocks (external), user selects a signal-line deep inside one of the linked blocks. For example, s/he opens main1.slx, navigates 3-4 levels inside link1 and selects a signal line.

Is there a way to get the handle and/or name of that selected line? The linked library is indeed an external model/block but I need to get its handle. Again, I've tried multiple options in find_system but they all return blanks.

Thanks again!

[Fangjun Jiang]

How about selecting a connected block and then get_param(BlockPath,'LineHandles')?

[Prabhakar Vallury]

The only way I've discovered is to loop through all the blocks in main1.slx and check if any of them have a selected signal and proceed from there. Checking for selected entities only from main1.slx does not work even if I use FollowLinks, SearchDepth, LookInsideReferenceSubsystems, etc. I'll upvote your answer, thanks for the help.

[Fangjun Jiang]

I am lost. This should not be that complicated.

Open main.slx, select that 'link1' block, which is an instance of your library block.

run 'BlockPath=gcb', this should give you the full block path of the library block in the main model

run lines=find_system(BlockPath,'FindAll','On', 'FollowLinks','On','LookUnderMasks','All','type', 'line')

[Prabhakar Vallury]

That is correct but I was hoping to programmatically get all line handles directly by querying main.slx with find_system. That doesn't work, so I have to loop through all the linked library blocks that exist within main.slx and get the line handles for each one. In this, I have to ignore annotation blocks, etc. as well. Makes it a little more convoluted, but that's okay. Would've been nice to get all handles from the top-level query, that's all I'm saying.

Thanks for the guidance.

[Fangjun Jiang]

I don't understand the problem. I dragged a "PID Controller" library block (it is a masked block) to a new empty model "untitled" and ran below. It found 160 line handles. All are inside the library block.

lines=find_system('untitled','FindAll','On', 'FollowLinks','On','LookUnderMasks','All','type', 'line')