There is no difference: at the end you will end up with a CPLEX object.
* With cplex package, you create and manipulate a problem via indexes and coefficients. So it is very mathematical.
* docplex is built on top of docplex and provides an object layer with variables, expressions, aggregate functions... which is easier to manipulate and maintain. It covers most CPLEX standard functionalities. Once your Model is built, you can use the get_cplex method to get the hand on the cplex object and use the cplex package functions if you need access to more expert methods such as the extreme ray.
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Vincent Beraudier
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