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- Problem instance
- ===================
- In this tutorial, we introduce the way of using **Macop** and running your algorithm quickly using the well known `knapsack` problem.
- Problem definition
- ~~~~~~~~~~~~~~~~~~~~~~
- The **knapsack problem** is a problem in combinatorial optimisation: Given a set of items, each with a weight and a value, determine the number of each item to include in a collection so that the total weight is less than or equal to a given limit and the total value is as large as possible.
- The image below provides an illustration of the problem:
- .. image:: ../_static/documentation/knapsack_problem.png
- :width: 40 %
- :align: center
- In this problem, we try to optimise the value associated with the objects we wish to put in our backpack while respecting the capacity of the bag (weight constraint).
- .. warning::
- It is a combinatorial and therefore discrete problem. **Macop** decomposes its package into two parts, which is related to discrete optimisation on the one hand, and continuous optimisation on the other hand. This will be detailed later.
- Problem implementation
- ~~~~~~~~~~~~~~~~~~~~~~~~~~~
- During the whole tutorial, the example used is based on the previous illustration with:
- .. image:: ../_static/documentation/project_knapsack_problem.png
- :width: 85 %
- :align: center
- Hence, we now define our problem in Python:
- - worth value of each objects
- - weight associated to each of these objects
- .. code-block:: python
-
- """
- Problem instance definition
- """
- elements_score = [ 4, 2, 10, 1, 2 ] # worth of each object
- elements_weight = [ 12, 1, 4, 1, 2 ] # weight of each object
- Once we have defined the instance of our problem, we will need to define the representation of a solution to that problem.
- Let's define the ``SimpleBinaryCrossover`` operator, allows to randomly change a binary value of our current solution.
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