要一直走下去

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列表:

L.append(x) # x追加到L尾部
L.count(x)  # 返回x在L中出现的次数
L.extend(m) # Iterable m的项追加到L末尾
L += m      # 功能同L.extend(m)
L.index(x, start, end) # 返回x在列表L(或者L[start:end])最左边出现的索引位置,否则报异常
L.insert(i, x) # 将x插入索引为i处
L.pop()     # 返回并移除L最右边的项
L.pop(i)    # 返回并移除索引为i的项
L.remove(x) # 从L中移除最左边的项x,找不到就抛异常
L.reverse() # 反转列表
L.sort(...) # 列表排序,参数可选

 

元祖:

'''
元祖可以类比字符串
元祖tuple的初始化
'''
t1 = tuple()
t2 = ()
t3 = "venus", -28, "green", 19.74
'''
元祖方法
'''
c = t3.count("green")  # 统计个数
i = t3.index(-28)      # 查看下标
'''
交换值
'''
a, b = 1, 2    # a=1, b=2
a, b = b, a    # a=2,  b=1
View Code

     命名元祖

'''
命名的元祖:计算商品总价
'''
from collections import namedtuple
Sale = namedtuple("Sale","productid customerid date quantity price")
sales = []
sales.append(Sale(432,921,"2008-09-14",3,7.99))
sales.append(Sale(419,874,"2008-09-15",1,18.49))
if __name__ == '__main__':
    total = 0
    for sale in sales:
        total += sale.quantity * sale.price
    print("Total ${0:.2f}".format(total))
View Code
'''
namedtuple("Foo","x y")函数返回tuple的子类,类名为Foo,属性为x y
'''
from collections import namedtuple
Aircraft = namedtuple("Aircraft","manufacturer model seating")
Seating = namedtuple("Seating","minimum maximum")
aircraft = Aircraft("Airbus", "A320-200", Seating(100, 200))
print(aircraft.seating.maximum)   # 200
print("{0} {1}".format(aircraft.manufacturer, aircraft.model))  # Airbus A320-200
print("{0.manufacturer} {0.model}".format(aircraft))            # Airbus A320-200
View Code

 

posted on 2018-07-06 09:40  要一直走下去  阅读(269)  评论(0编辑  收藏  举报