python - 在具有大量输入的 for 循环上实现 Pool

Question

我一直在尝试改进我的代码(使用 numba 和多处理)，但我不太明白，因为我的函数有很多参数。

我已经用其他函数简化了它(见下文)...

由于每个代理(类实例)对于这些操作都是相互独立的，因此我想将 for 替换为 Pool。

所以我会得到一个大函数pooling()，我将调用它并传递代理列表

from multiprocessing import Pool

p = Pool(4)
p.map(pooling, list(agents))

但是，我在哪里添加池函数需要的所有参数？

事实上:

def check_demographics(month, my_agents, families, firms, year, mortality_men, mortality_women, fertility, state_id):

    dummy = list(my_agents)
    d = str(state_id.iloc[0])

# Place where I would like to replace the LOOP. All below would be a function 

    for agent in dummy:

        if agent.get_region_id()[:2] == d:

            # Brithday
            if month % 12 == agent.month - 1:
                agent.update_age()

            # Mortality probability 
            if agent.get_gender() == 'Male':
                prob = mortality_men[mortality_men['age'] == agent.get_age()][year].iloc[0]

            # When gender is Female
            else:
                # Extract specific agent data to calculate mortality 'Female'
                prob = mortality_women[mortality_women['age'] == agent.get_age()][year].iloc[0]

            # Give birth decision 
                age = agent.get_age()
                if 14 < age < 50:
                    pregnant(agent, fertility, year, families, my_agents)

            # Mortality procedures 
            if fixed_seed.random() < prob:
                mortal(my_agents, my_graveyard, families, agent, firms)

这是我的程序中最耗时的函数。@jit 并没有多大帮助。

非常感谢

Answer 1

是的，有很多参数!考虑使用类。

好吧，由于 Pool.map 仅支持一个可迭代参数，因此您需要将所有内容分组到一个位置。我建议您使用“Facade”模式:一个中间类，用于存储所有必需的参数，并具有一个不带参数的方法(我称之为 check)(它是一个方法)。

class Facade(object):
    def __init__(self, agent, d, families, fertility, firms, month, mortality_men, mortality_women, my_agents,
                 my_graveyard, year):
        self.agent = agent
        self.d = d
        self.families = families
        self.fertility = fertility
        self.firms = firms
        self.month = month
        self.mortality_men = mortality_men
        self.mortality_women = mortality_women
        self.my_agents = my_agents
        self.my_graveyard = my_graveyard
        self.year = year

    def check(self):
        (agent, d, families, fertility, firms,
         month, mortality_men, mortality_women,
         my_agents, my_graveyard, year) = (
            self.agent, self.d, self.families, self.fertility, self.firms,
            self.month, self.mortality_men, self.mortality_women,
            self.my_agents, self.my_graveyard, self.year)
        if agent.get_region_id()[:2] == d:

            # Brithday
            if month % 12 == agent.month - 1:
                agent.update_age()

            # Mortality probability
            if agent.get_gender() == 'Male':
                prob = mortality_men[mortality_men['age'] == agent.get_age()][year].iloc[0]

            # When gender is Female
            else:
                # Extract specific agent data to calculate mortality 'Female'
                prob = mortality_women[mortality_women['age'] == agent.get_age()][year].iloc[0]

                # Give birth decision
                age = agent.get_age()
                if 14 < age < 50:
                    pregnant(agent, fertility, year, families, my_agents)

            # Mortality procedures
            if fixed_seed.random() < prob:
                mortal(my_agents, my_graveyard, families, agent, firms)

备注:我的重构确实很丑陋，但为了清晰起见，我想保持变量名称不变。

那么你的循环可以是这样的:

def check_demographics(month, my_agents, families, firms,
                       year, mortality_men, mortality_women,
                       fertility, state_id, my_graveyard):
    d = str(state_id.iloc[0])
    pool = Pool(4)
    facades = [Facade(agent, d, families, fertility, firms,
                      month, mortality_men, mortality_women,
                      my_agents, my_graveyard, year)
               for agent in my_agents]
    pool.map(Facade.check, facades)

您说每个代理彼此独立，但是在分析循环后，我发现您需要完整的代理列表(my_agents 参数)。对于Facade 类来说这是显而易见的。因此，您的代理列表不得更改，并且每个代理的内部状态必须在循环期间卡住。