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Repo info
    Werner Van Geit
    In any case, as you can see, atm
    if alpha is None:
    alpha = len(population)
    so would should leave the alpha parameter alone ftm
    Russell Jarvis
    Hi Werner and others, I am just wondering how you can execute a custom defined evaluate method with arguments in a for loop? In all of the examples I have seen the evaluate method is kind of made available to call from the GA with a statement like:
    toolbox.register("evaluate", evaluate)
    Russell Jarvis
    However for multiple different reasons I would like to execute a genetic algorithm in a loop. And I would like to tune a different number of parameters in a model in different iterations in a for loop.
    Is there an alternative syntax for calling the evaluate method with arguments?
    I will paste an example below:
    for i in parameters:
    from scoop import futures
    for i in parameters:
    if name == 'main':
    toolbox = base.Toolbox()
    toolbox.register("map", futures.map)
    toolbox.register("uniformparams", uniform, LOWER, UPPER, IND_SIZE)
    creator.create("Individual", Individual, fitness=creator.FitnessMin)
    toolbox.register("population", tools.initRepeat, list, toolbox.Individual) #toolbox.register("evaluate",toolbox.Individual,target_versus_error,target_versus_errorls,IND_SIZE)
    toolbox.register("evaluate",evaluate) toolbox.register("mate",deap.tools.cxSimulatedBinaryBounded,eta=ETA,low=LOWER,up=UPPER)
           # Register the mutation operator
           # Experiment with changing the strategy.
           toolbox.register("mutate", deap.tools.mutPolynomialBounded, eta=ETA,low=LOWER, up=UPPER, indpb=0.1)
           # Register the variate operator
           toolbox.register("variate", deap.algorithms.varAnd)
           #select the best 
           sel=toolbox.register("select", ind_selector, selector=tools.selBest)
           # Generate the population object
           pop = toolbox.population(n=MU)
           hof = tools.HallOfFame(1)
           stats = tools.Statistics(lambda ind: ind.fitness.values)
           for gen in range(NGEN):
               offspring = algorithms.varAnd(pop, toolbox, cxpb=CXPB, mutpb=1-CXPB)
               fits = toolbox.map(toolbox.evaluate, offspring)
               for fit, ind in zip(fits, offspring):             
                   ind.fitness.values = fit
                   print ' generation # ', gen
                   print ' fitness, index ', fit, ind, offspring
               pop = toolbox.select(offspring, k=len(pop))
           top10 = tools.selBest(pop, k=10)
    Russell Jarvis
    Sorry about the formatting above.
    I would like the line toolbox.register("evaluate",evaluate) to be a more flexible call to my custom evaluate method, which executes with different values depending on the current index of the top level for loop: for i in parameters:
    Russell Jarvis
    One reason I want to execute a GA in a for loop is because I want to do a small sweep of possible GA parameters: population_size,offspring_size, cross_over_rate, mutation_rate etc. Another reason I would like to be able to call evaluate with changing arguments is because I would like to execute the GA by launching python with different command line arguments each time it starts, and I want the number of parameters to be optimised to be different on different launches.
    Russell Jarvis
    For this reason I have been trying to learn from the BluePyOpt source code. I have noticed that the opt_l5pc file can be launched with command line arguments, and also that it must therefore must be able to execute the evaluator method using different arguments according to different contexts. However I don't understand how this works. Using grep I found the file tests/test_evaluators.py: and the line evaluator = bluepyopt.evaluators.Evaluator(). I then opened the file: evaluators.py. I can see that this file implements an abstract method somehow, and I think that the existence of this file is the reason why bluepyopt is able call the evaluate method with different parameters as appropriate. However I have never seen abstract methods before and I don't understand the evaluators.py file and what it does, I would just like to know: Am I on the right track? Is there a simpler approach (things seem to be much too complicated for something which should be much more simple)?
    Werner Van Geit
    hi @russelljjarvis, am at a FENS workshop atm, and the answer is a bit complex. I'll answer as soon as find some time.
    Russell Jarvis
    Great. That would be awesome thanks:) This issue is still a priority for me.
    Russell Jarvis
    Do you think that I can use a function decorator as a way of feeding a flexible number of parameter arguments to the evaluate function? For instance the function tupleize could instead be a different kind of wrapper which provides a flexible number of parameters to optimise to evaluate?
    def tupleize(func): """A decorator that tuple-ize the result of a function. This is useful when the evaluation function returns a single value. """ def wrapper(*args, **kargs): return func(*args, **kargs), return wrapper def main(func, dim, maxfuncevals, ftarget=None): toolbox = base.Toolbox() toolbox.register("update", update) toolbox.register("evaluate", func) toolbox.decorate("evaluate", tupleize)
    Russell Jarvis
    It turns out it was much simpler to give the evaluate method a flexible number of parameters. I changed the evaluate method signature to look like this now def evaluate(individual,IND_SIZE):
    and its called like this toolbox.register("evaluate", evaluate,IND_SIZE=IND_SIZE)
    Werner Van Geit
    @russelljjarvis regarding your question of Jul 1. Am not completely sure I understand the goal of your question. Do you want to create your own evaluator ?
    @russelljjarvis regarding your last comment. Not sure you really need to change the number of parameters this way ?
    the idea is that you create a new Evaluator class, for your specific problem. this class should have a field 'params' which consists of a list of Parameter objects
    BluePyOpt will deduce the number of parameters from the length of the above list
    For an example on how to create an Evaluator, you can have a look at this example: https://github.com/BlueBrain/BluePyOpt/blob/master/examples/graupnerbrunelstdp/gbevaluator.py
    Russell Jarvis
    Hi Werner, Yes thats right I did want to create my own evaluator. I succeeded in doing that okay. I was trying to figure out exactly what piece of BluePyOpt code was responsible for deducing the number of parameters from params object as I was trying to achieve that functionality myself. Currently I have achieved this functionality by passing a parameter dictionary to the evaluator and assinging parameters to HOC variables by iterating through the dictionary items. I did this by defining a method as such: def evaluate(individual,param_dict,tve={},tvel=[]):
    Registering the method: toolbox.register("evaluate", evaluate,param_dict=param_dict,tve=target_versus_error,tvel=target_versus_errorls)
    and then calling the method fitnesses = toolbox.map(toolbox.evaluate, population)
    Russell Jarvis
    Unfortunately I could not make BluePyOpt work, and it was easier for me to learn how to use DEAP directly.