GAMS World Forum

Hi, You can represent the matrix as a 2-dimensional GAMS parameter using the following code: from gams import * A=[[0., 0., 0., 0., 0.], [0., 0., 0., 0., 0.], [0., 0., 0., 0., 0.], [0., 0., 0., 1., 0.], [0., 0., 0., 0., 1.]] ws = GamsWorkspace(".") db = ws.add_database('data') mat = db.add...

Renger, First of all we need to distinguish between the use of the GAMS Python API and the GAMS Embedded Code Facility . While the GAMS Python API is provided for different version of Python, the Embedded Code Facility requires a Python 3.6 right now. The error message comes from the setup.py script...

Hello, There is currently no time schedule for updates of the Python version that is shipped with GAMS. It is primarily meant to be used as a minimal Python interpreter for certain GAMS features, especially the Embedded Code Python Facility. If there is a need for specific Python configurations, a s...

This is not possible right now. In order to get detailed information about an error it is required to have a look into the listing file or to examine the log output.

Best,
Clemens

The log output can be captured by specifying the output argument in GamsJob.run() . The following code snipped shows how to get the log output redirected to stdout: from gams import * import sys if __name__ == "__main__": if len(sys.argv) > 1: ws = GamsWorkspace(system_directory = sys.argv...

Hello, The GamsException itself as well as the GamsExceptionExecution do not give you detailed information about the cause of an error. You can use the GamsException.get_rc() call in order to get the return code of GAMS which tells you what kind of problem occurred. See the documentation for possibl...

Bruno, Sorry for the delay. It seems to me that you did solve your original problem where you did the mi.instantiate call multiple times. So from a GAMS/Python perspective the code looks actually correct to me. The new problem that arises now is that you also want to do some calculations in MatLab &...

Bruno, You do not have to call those methods multiple times. After you have instantiated your GamsModelinstance you have also defined the symbols that you want to change (GamsModifier). All you have to do is to change the data in your symbol (ySp) and call mi.solve(). Can you can provide a larger ex...

Bruno, You might want to have a look at the transport7.py example: https://www.gams.com/latest/docs/apis/examples_python/transport7_8py_source.html This shows how you can use the GamsModelinstance class. More information is available in the documentation: https://www.gams.com/latest/docs/apis/python...

Serdar,

This is actually a bug in the GAMS Python API. We have already fixed the bug and will publish it in the next GAMS release. Thank you very much for reporting this problem.

Best,
Clemens