Support for multiple vensim views

[JamesPHoughton]

Hey @enekomartinmartinez - do we have support for multiple views at the moment? Is there a test in the test-models that demonstrates this?

[enekomartinmartinez]

Yes, having more than one view doesn't change the translation. As the equations are written in the first part of the mdl file where there are no differences between views.

The views are only defined in the sketch part, in fact we support parsing the sketch to identify the different views and classify the variables in different files depending on which view they are present. It also allows multi-level for example if you have the views:

economy.usa-imports
economy.usa-exports
economy.eu-imports
economy.eu-exports
economy.china-imports
economy.china-exports
energy.usage
energy.production

This could be identified with the separators [".", "-"] and therefore produce the following file structure

modules

• economy
  • usa
    • imports.py
    • exports.py
  • eu
    • imports.py
    • exports.py
  • china
    • imports.py
    • exports.py
• energy
  • usage.py
  • production.py

Check the documentation https://pysd.readthedocs.io/en/master/advanced_usage.html#splitting-vensim-views-in-separate-python-files-modules

This feature is tested using the models in the following folder: https://github.com/JamesPHoughton/pysd/tree/master/tests/more-tests
With the following script: https://github.com/JamesPHoughton/pysd/blob/master/tests/pytest_translators/pytest_split_views.py

[hyunjimoon]

@enekomartinmartinez May I ask whether this feature has been added recently? Last time I checked it wasn't there (perhaps I was mistaken) and the test script https://github.com/SDXorg/pysd/blob/master/tests/pytest_translators/pytest_split_views.py is from 16 days ago. (In either way, if we can do this, this is definitely a good news.)

[enekomartinmartinez]

It was added more than a year ago in PySD 1.9.0.
The date of 16 days ago corresponds to some fixes made in the building of the split model in PySD 3.6.0, which required some new tests.

Note that when you require the VensimFile to split by views, this parses the sketch and returns a dictionary with the views as keys and workbench variables (shadow variables are omitted) as values. This dictionary will be nested if you pass a subviews separator.
See

pysd/pysd/translators/vensim/vensim_file.py

Line 142 in 975a076

def parse_sketch(self, subview_sep: List[str]) -> None:

Then the dictionary is used to classify the variables in modules when building the section.
See

pysd/pysd/builders/python/python_model_builder.py

Line 215 in 975a076

def _build_modular(self, elements_per_view: dict) -> None: