I need to solve a model with multiple varying data (thus the use of GamsModelInstance) several times with varying accuracy (start at lower accuracy and progress towards OptCr=0).
As far as I am aware, the OptCr option is set for the GamsCheckpoint from which the GamsModelInstance is created.
Recreating a new GamsModelInstance (with all the Modifiers, instantiation etc.) each time the solution tolerance needs to be tightened seems a bit unwieldy.
Is it possible to directly change these parameters for the existing GamsModelInstance, without re-instantiation?
You will need to solve the instance with a solver option file that sets the option for relative optimality before the solve method. You can pass a GamsModelInstanceOpt object to the solve method to instruct the solve to process the solver option file (see https://www.gams.com/latest/docs/apis/python/classgams_1_1execution_1_1GamsModelInstance.html#a29532f501f4cfc8f15b7ecb9ac9f6bab and https://www.gams.com/latest/docs/apis/python/classgams_1_1execution_1_1GamsModelInstanceOpt.html).
-Michael