Hands-On Genetic Algorithms with Python

Defining the fitness strategy

To help define this strategy, DEAP comes with the abstract base.Fitness class, which contains a weights tuple. This tuple needs to be assigned with values in order to define the strategy and make the class usable. This is done by extending the base Fitness class using the creator, in a similar manner to what we did with the preceding Developer class:

creator.create("FitnessMax", base.Fitness, weights=(1.0,))

This will yield a creator.FitnessMax class extending the base.Fitness class, with the weights class attribute initialized to a value of (1.0,).

Note the trailing comma in the weights definition when a single weight is defined. The comma is required because weights is a tuple.

The strategy of this FitnessMax ...