import logging # Generic algorithm class class Algorithm(): def __init__(self, _initalizer, _evaluator, _updators, _policy, _validator, _maximise=True): """ Initialize all usefull parameters for problem to solve """ self.initializer = _initalizer self.evaluator = _evaluator self.updators = _updators self.validator = _validator self.policy = _policy # other parameters self.maxEvalutations = 0 # by default self.maximise = _maximise self.initRun() def initRun(self): """ Reinit the whole variables """ self.currentSolution = self.initializer() # evaluate current solution self.currentSolution.evaluate(self.evaluator) # keep in memory best known solution (current solution) self.bestSolution = self.currentSolution self.numberOfEvaluations = 0 def evaluate(self, solution): """ Returns: fitness score of solution which is not already evaluated or changed Note: if multi-objective problem this method can be updated using array of `evaluator` """ return solution.evaluate(self.evaluator) def update(self, solution): """ Apply update function to solution using specific `policy` Check if solution is valid after modification and returns it Returns: updated solution """ sol = self.policy.apply(solution) if(sol.isValid(self.validator)): return sol else: print("New solution is not valid", sol) return solution def isBetter(self, solution): """ Check if solution is better than best found Returns: `True` if better """ # depending of problem to solve (maximizing or minimizing) if self.maximise: if self.evaluate(solution) > self.bestSolution.fitness(): return True else: if self.evaluate(solution) < self.bestSolution.fitness(): return True # by default return False def run(self, _evaluations): """ Run the specific algorithm following number of evaluations to find optima """ self.maxEvalutations = _evaluations self.initRun() logging.info("Run %s with %s evaluations" % (self.__str__(), _evaluations)) def progress(self): logging.info("-- Evaluation n°%s of %s, %s%%" % (self.numberOfEvaluations, self.maxEvalutations, "{0:.2f}".format((self.numberOfEvaluations) / self.maxEvalutations * 100.))) def information(self): logging.info("-- Found %s with score of %s" % (self.bestSolution, self.bestSolution.fitness())) def __str__(self): return "%s using %s" % (type(self).__name__, type(self.bestSolution).__name__)