Question

以下是我倾向于在这里和那里使用的“模式”的略微简化示例。

class Indicator(object):

    def __init__(self):
        self.list1 = []

    instances = {}

    @classmethod
    def get_instance(cls, date, hour, hostname, action):
        if (date, hour, hostname, action) in Indicator.instances:
            i = Indicator.instances[(date, hour, hostname, action)]
        else:
            i = cls()
            Indicator.instances[(date, hour, hostname, action)] = i
        return i

    def add_data_point(self, foo):
        self.list1.append(foo)

    def get_avg(self):
        return sum(self.list1) / len(self.list1)

Indicator.get_instance("2015-01-01", "12", "host1", "foo1").add_data_point(23)
Indicator.get_instance("2015-01-01", "12", "host1", "foo1").add_data_point(-5)
Indicator.get_instance("2015-01-01", "12", "host1", "foo1").add_data_point(12)
Indicator.get_instance("2015-01-01", "12", "host1", "foo1").add_data_point(6)
Indicator.get_instance("2015-01-01", "12", "host2", "foo1").add_data_point(2322)
Indicator.get_instance("2015-01-01", "12", "host2", "foo1").add_data_point(-52)
Indicator.get_instance("2015-01-01", "12", "host2", "foo1").add_data_point(232)
Indicator.get_instance("2015-01-01", "12", "host2", "foo1").add_data_point(34)

for indicator_id in Indicator.instances:
    print('For {0} average is {1}'.format(indicator_id, Indicator.instances[indicator_id].get_avg()))

由于这似乎是我经常做的事情，我很想相信有更好/更简单的方法来使用python（2.6）。有吗？

Answer 1

我认为这会更好。更新逻辑以进行初始化。

#-*- coding:utf-8 -*-
#!/usr/bin/env python


class Indicator(object):

    def __init__(self):
        self.list1 = []

    instances = {}

    @classmethod
    def get_instance(cls, hostname, date="2015-01-01", hour="12", action="fool"):
        if not (date, hour, hostname, action) in Indicator.instances:
            Indicator.instances[(date, hour, hostname, action)] = cls() # you only need to initialize when there is no match
        return Indicator.instances[(date, hour, hostname, action)]

    def add_data_point(self, foo):
        self.list1.append(foo)

    def get_avg(self):
        return sum(self.list1) / len(self.list1)
# use list comprehension to initialize instances    
[i.add_data_point(x) for i,x in zip(map(Indicator.get_instance(), ['host1', 'host1', 'host1', 'host1', 'host2', 'host2', 'host2', 'host2']), [23, -5, 12, 6, 2322, -52, 232, 34])]

for indicator_id in Indicator.instances:
    print('For {0} average is {1}'.format(indicator_id, Indicator.instances[indicator_id].get_avg()))

我应该如何存储和操作要报告的数据？

1 个答案: