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[bknueven]

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[jasperstoter]

I have just started using mpi-sppy and I have build an two stage Extensive Form stochastic model. I was wondering if there is a way to acces the solutions that the model creates. In the farmer example ef.get_root_solution() and ef.get_objective_value() to get the root decision variables and objective. However i would also like to see what the second stage decision variables are. Are there any examples this being done?

[jasperstoter]

I manage to acces the scenario solutions for the extensive form model by using the following command
[*output] = ef.scenarios()
which gives a list of tuples with the name and model for every scenario

[DLWoodruff]

Take a look at this and let me know if this does the trick: https://mpi-sppy.readthedocs.io/en/latest/access_solutions.html

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On Wed, Feb 15, 2023 at 4:51 AM jasperstoter ***@***.***> wrote: I have just started using mpi-sppy and I have build an two stage Extensive Form stochastic model. I was wondering if there is a way to acces the solutions that the model creates. In the farmer example ef.get_root_solution() and ef.get_objective_value() to get the root decision variables and objective. However i would also like to see what the second stage decision variables are. Are there any examples this being done? — Reply to this email directly, view it on GitHub <#228 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AD4VTBHLIHLLGSM2PVS3QDDWXTGOPANCNFSM5RD4MD7Q> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[jasperstoter]

Thank you for the fast reply! For the Extensive form the method described worked and i could acces the results. However I did not understand how to use the wheelspinner and write_tree_solution functions that you suggested. Now i am trying to solve the model using progressive hedging for which i cant use the EF method. Could you give a example on how to do this?

[DLWoodruff]

Most of the examples have a file called E_cylinders.py that relies on E.py. For example,
examples/sizes/sizes_cylinders.py and examples/sizes/sizes.py
The documentation on readthedocs also has some background information.

[jasperstoter]

Is it possible to add a time limit to the progressive hedging algorithm? For pyomo models the time limit can be passed to the server in the solver options. I however cant find a similar function of the progressive hedging algorithm

[DLWoodruff]

You can give an iteration limit, but no one has yet implemented a time limit. Dave

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On Mon, May 15, 2023 at 10:35 PM jasperstoter ***@***.***> wrote: Is it possible to add a time limit to the progressive hedging algorithm? For pyomo models the time limit can be passed to the server in the solver options. I however cant find a similar function of the progressive hedging algorithm — Reply to this email directly, view it on GitHub <#228 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AD4VTBDAVOIKTINKWS2SU4LXGMGZPANCNFSM5RD4MD7Q> . You are receiving this because you commented.Message ID: ***@***.***>