SugarAgent.py

""" Adpated from Think Complexity 2 edition by Allen Downey (thank you very much).
    Available at https://github.com/AllenDowney/ThinkComplexity2/blob/master/code/chap09.ipynb
    Copyright 2016 Allen Downey, MIT License
    """

import numpy as np


class Agent:

    def __init__(self, loc, params):
        """Creates a new agent at the given location.

        loc: tuple coordinates
        params: dictionary of parameters
        """
        self.loc = tuple(loc)
        self.age = 0

        # extract the parameters
        max_vision = params.get('max_vision', 6)
        max_metabolism = params.get('max_metabolism', 4)
        min_lifespan = params.get('min_lifespan', 10000)
        max_lifespan = params.get('max_lifespan', 10000)
        min_sugar = params.get('min_sugar', 5)
        max_sugar = params.get('max_sugar', 25)

        # choose attributes
        self.vision = np.random.randint(1, max_vision)
        self.metabolism = np.random.uniform(1, max_metabolism)
        self.lifespan = np.random.uniform(min_lifespan, max_lifespan)
        self.sugar = np.random.uniform(min_sugar, max_sugar)

    def step(self, env):
        """Look around, move, and harvest.

        env: Sugarscape
        """
        self.loc = env.look_and_move(self.loc, self.vision)
        self.sugar += env.harvest(self.loc) - self.metabolism
        self.age += 1

    def is_starving(self):
        """Checks if sugar has gone negative."""
        return self.sugar < 0

    def is_old(self):
        """Checks if lifespan is exceeded."""
        return self.age > self.lifespan