Error: cplex (default) cannot extract expression; OPL cannot extract expression AND change interface language

1
votes

I'm a total beginner with CPLEX and OPL, so maybe someone can help me with the coding of a mixed integer programming model. I finished the model and the data. When I run the configuration I get 44 errors, including "opl cannot extract expression", "CPLEX (default) cannont extract expression" for my objective function and some of the constraints. I really do not know how to solve these errors, so maybe someone can help me out here.

Unfortunately, my interface language is German. Can someone tell me how to change it to English so I can post the errors in a language more people can understand?

Here you can find the code of the objective function and the constraints that are named in the error section, and a screenshot of the errors (in German).

model enter image description here

1
cplexopl

1 Answers

1
votes

First, to launch the cplex opl ide in English you may do in command line oplide -nl en and see

https://www.ibm.com/support/knowledgecenter/SSSA5P_12.8.0/ilog.odms.ide.help/OPL_Studio/globalization/topics/opl_globaliz_overriding_settings.html

for more.

Now about your error, cannot extract. Are your constraints linear? I see a product and I d like to remind you that if x and y are decision variables then x times y is not linear.

PS: there's a similar question at https://developer.ibm.com/answers/questions/494538/error-cplex-default-cannot-extract-expression-opl.html?utm_campaign=answers&utm_medium=email&utm_source=answers-new-question&utm_content=answers-answer-question++