Regarding scip.Model.getState() for extracting the state of the solver

[XiangyuYang-Opt]

Hi, all,

I want to ask that what the alternatives are for the function scip.Model.getState()? It seems that .getState() is an old-fashioned usage, and it is not available to see on Model Class Reference (i.e., on SCIP Official website) anymore. Could anyone help with this?

Thanks in advance.

[gasse]

Hi @XiangyuYang-Opt ,

The alternative in Ecole is the NodeBipartite observation, available here:
https://doc.ecole.ai/py/en/stable/reference/observations.html#node-bipartite

It basically extracts the same information, but has been re-engineered in C++ (including also minor bug fixes that were present in the original getState()).

Best,
Maxime

[XiangyuYang-Opt]

Thanks @gasse for replying!

Further, I would like to ask if the original code for model.getState() can be provided in this project? As I understand, this model.getState() method is coded by yourself and is integrated into the SCIPopt package, e.g., the scip.pyx file.

Thanks.

[gasse]

You will find that function in a dedicated ml-branching branch in our PySCIPOpt fork here:
https://github.com/ds4dm/PySCIPOpt/blob/9b88eddcfe99208e737236d39ccd6c9dd1a9bec4/src/pyscipopt/scip.pyx#L3917

Best,
Maxime

[LeonaireHo]

Hi, @gasse
Hello, after I installed it with your github branch, it still couldn't find the function getState in scip.Model. Is it normal? What else do I need to configure?

Thanks in advance.

[gasse]

Hi @LeonaireHo . Most likely you've installed from the main branch. The getState() function is only available in the ml-branching branch. You should be able to install using:

pip install git+https://github.com/ds4dm/PySCIPOpt.git@ml-branching

[FosingC]

Hi @gasse , when use the command pip install git+https://github.com/ds4dm/PySCIPOpt.git@ml-branching , the error information showed below:
gcc -pthread -B /home/zhangliang/anaconda3/envs/rl11/compiler_compat -Wl,--sysroot=/ -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -I/tmp/pip-req-build-okb3jayy/include -I/home/zhangliang/anaconda3/envs/rl11/lib/python3.6/site-packages/numpy/core/include -I/home/zhangliang/anaconda3/envs/rl11/include/python3.6m -c src/pyscipopt/scip.c -o build/temp.linux-x86_64-3.6/src/pyscipopt/scip.o
src/pyscipopt/scip.c:648:10: fatal error: scip/scip.h: No such file or directory
648 | #include "scip/scip.h"
| ^~~~~~~~~~~~~
compilation terminated.
error: command 'gcc' failed with exit status 1
----------------------------------------
how can I solve it? Thanks!