Seth on SimulinkAugust 11th, 2009How Many Blocks are in that Model?My colleague Sam and I wanted to find an example model with about 10,000 blocks. I suggested the HL-20 model from the Aerospace Blockset, asbhl20.mdl. Sam decided to measure the total number of blocks by running sldiagnostics: >> [t,s] = sldiagnostics('asbhl20','CountBlocks');
Sam quickly sent me a message saying that the HL-20 model only had 5700 blocks. What gives? What is SLDIAGNOSTICS? First, let us discuss a little history of sldiagnostics. Over the years, Simulink developers have worked with many customers to learn about their modeling styles and assist in debugging problems. Unfortunately some customers are unable to share their models because they might contain proprietary information. The solution these developers created were a series of scripts that would quickly gather information about a model without any model algorithm information. These collected scripts then became the sldiagnostics function. Because the output of these scripts was generally devoid of any proprietary data, even customers who could not share their models were able to provide the diagnostic information instead. Most of the checks done by sldiagnostics help you gather an understanding of the model as a whole. This is a great help in learning about models rather than having to browse through every system one-by-one. CountBlocks The diagnostic information Sam gathered was the output of CountBlocks. Here is a part of the text report for the HL-20 model. Finished counting blocks in 'asbhl20'.
HL-20 Includes Model Reference The HL-20 model includes 9 ModelReference blocks. (I introduced some of the basics of model reference a previous post.) You can see the hierarchy of the model in the Dependency Viewer instance view.
When I think about a model, I imagine the net collected functionality represented by it. I think the number of blocks used to create that model is a simple measure for how much functionality/algorithm there is. Model reference blocks contain the functionality of the entire model that they reference, however, sldiagnostics counts ever Model Reference block as only one block. The measure I am really looking for is the subsystem equivalent implementation of all the blocks in the model. To get this for the HL-20 model, you actually need to count the blocks inside each model referenced and multiply by the number of instances. I wrote a MATLAB function to do this: function totalBlocks =
mdlrefCountBlocks(mdl)
Total Blocks Here are the results of running this function: >> total = mdlrefCountBlocks('asbhl20');
Now it’s your turn In the end, we can see the HL-20 model has almost 11K blocks. Do you use model reference? How many total blocks are in the hierarchy of your largest model? Use the script above to gather this data and post it in the comments here. 8 Responses to “How Many Blocks are in that Model?”Leave a Reply |
|
|||
|
These postings are the author's and don't necessarily represent the opinions of The MathWorks. |
Seth,
There are two related items I’d like to be able to generate from a script - the model’s cyclomatic complexity and the block sort order. Is there any way to return these to a workspace variable using a script?
@Seth, Interestingly this functions counts blocks inside of library Simulink subsystems, but not objects inside of library Stateflow charts. Is there way to work around this?
Hi Seth,
It may be of interest to our users that someone in MathWorks Consulting has uploaded a script which does something similar as the above, except it goes inside nested model reference blocks. (http://www.mathworks.com/matlabcentral/fileexchange/20568) Your script above may be able to do the same if find_mdlrefs(mdl,true) is used.
Whoops, I wrote too soon. The second parameter of find_mdlrefs defaults to true, so your code will also find nested model references.
@Gen - Thanks for the link to the file Gen!
@Wei, Stateflow metrics for a model are obtained via the ‘CountSF’ option of sldiagnostics.
@Rob,
1. The difference I said was about counting library linked Simulink blocks vs. Stateflow objects (states, junction, etc.) with ‘CountBlocks’ or ‘CountSF’. sldiagnostics counts number of linked charts, nothing further.
2. sldiagnostics doesn’t work on block diagram library model, including Stateflow or not. A simple enhancement to add in future release.
Hi,
in the introductory example for fuzzy logic toolbox it was noted that using non fuzzy means, you could “Specify that service accounts for 80% of the overall tipping grade and the food makes up the other 20%”. Can you do this using the fuzzy logic toolbox of matlab. Can you give weights to diffrenet inputs.