Access to value of constraint variable at the end of model.optimize?

[janpeter19]

Checklist

• I searched the documentation.
• I looked through similar issues on GitHub.
• I looked up "How to do ... in optlang" on a search engine.

Question

I am a new user to Opltang and just used it for smaller problems, mainly linear-programming.
It would be very convenient to have access to the actual value of a constraining variable at the
end of an optimisation. The actual objectiv as well as variables I can get but I do not see
how to read out the value of the constraint. Can you help me?

Examples:
model.objective.value - ok
model.variables.x_opt.primal - ok
model.constraints.y_lim.value - not ok
model.constraints.y_lim.primal - not ok

[cdiener]

As long as y_lim is the name of the constraint the last option should work. What error are you getting?