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BCVTB: how to install new python modules?

asked 2016-06-27 12:27:59 -0600

I've created a control algorithm in Python that is leveraging some modules such as Numpy or PuLP (for interfacing for MILP solver GLPK).

I was trying to use the Building Control Virtual Test Bed and the underlying Ptolemy, but so far I've found it really hard to use and not user friendly at all, the lack of examples and tutorials out there is really not helping. Anyways, among the many hurdles I'm facing, there's one that will be a deal breaker for me: whether I can actually run my program or not. Note that I could do without NumPy since I know it's problematic at best on Jython but I could not do without PuLP.

It seems that Ptolemy is using some kind of weird Jython. Is there any way to use the system python instead? Or can you install new python modules to Jython?

Alternatively, are there any workarounds I could use?

(at this point I'd even accept a dirty workaround such as exporting values to a csv, call a shell command to execute my system python with my given program, and reimport the value from the CSV?)

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answered 2016-06-27 13:52:00 -0600

updated 2016-06-27 15:33:52 -0600

The python actors rely indeed on Jython and have thus the limitations you encountered. Have you tried using the SystemCommand actor which allows to call any script?

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I wasn't aware of this component, thanks! I will try to use it, that if I can figure out how to log my variables into a csv file. There's a CSVWriter module, but after an hour and a half I couldn't make it work. Bad data types, and couldn't even figure how to pass the "filename" argument.

Julien Marrec gravatar image Julien Marrec  ( 2016-06-27 15:33:33 -0600 )edit

Hi, were you able to use the SystemCommand Actor for python script ?

niharkopal gravatar image niharkopal  ( 2017-06-06 00:52:58 -0600 )edit

Yeah I ended up using it to call my own system python.

Julien Marrec gravatar image Julien Marrec  ( 2017-06-06 03:05:46 -0600 )edit

Hi thanks a lot for replying. I have python 2.7 installed through conda on my system. And I plan to use numpy, theano libraries. So can you please guide me as to how you called your own system python through bcvtb ?

niharkopal gravatar image niharkopal  ( 2017-06-06 03:55:13 -0600 )edit

Figure 5.36 in the link given by Thierry is pretty clear.

Actually in my specific case I now remember what I've really done: I had to trigger my python script every day of the simulation at midnight only, and I couldn't do that with the systemCommand actor. So I used a PythonActor, and I would test if it was midnight, if so I would use subprocess.Popen to run a python script file with my local Anaconda python.

Julien Marrec gravatar image Julien Marrec  ( 2017-06-06 04:07:36 -0600 )edit

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Asked: 2016-06-27 12:27:59 -0600

Seen: 762 times

Last updated: Jun 27 '16