59 lines
1.4 KiB
Python
59 lines
1.4 KiB
Python
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#!/usr/bin/env python
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# -*- encoding: utf-8 -*-
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"""
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Topic: 通过名称访问序列
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Desc :
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"""
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from collections import namedtuple
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def name_seq():
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subscriber = namedtuple('Subscriber', ['addr', 'joined'])
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sub = subscriber('jonesy@example.com', '2012-10-19')
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print(sub)
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print(sub.addr, sub.joined)
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print(len(sub))
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addr, joined = sub
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print(addr, joined)
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def compute_cost(records):
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total = 0.0
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for rec in records:
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total += rec[1] * rec[2]
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return total
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def compute_cost2(records):
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Stock = namedtuple('SSS', ['name', 'shares', 'price'])
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total = 0.0
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for rec in records:
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st = Stock(*rec)
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total += st.shares * st.price
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s = Stock('ACME', 100, 123.45)
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# 更新命名元组
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s = s._replace(shares=75)
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print(s)
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return total
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Stock1 = namedtuple('Stock', ['name', 'shares', 'price', 'date', 'time'])
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# Create a prototype instance
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stock_prototype = Stock1('', 0, 0.0, None, None)
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# Function to convert a dictionary to a Stock
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def dict_to_stock(s):
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return stock_prototype._replace(**s)
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def default_stock():
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a = {'name': 'ACME', 'shares': 100, 'price': 123.45}
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print(dict_to_stock(a))
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b = {'name': 'ACME', 'shares': 100, 'price': 123.45, 'date': '12/17/2012'}
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print(dict_to_stock(b))
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if __name__ == '__main__':
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name_seq()
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# rs = [('aa', 12, 33)]
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rs = [['aa', 12, 33]] # 元组和序列都可以
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print(compute_cost2(rs))
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default_stock()
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