python学习笔记——列表操作

Posted 2020-09-27

python列表操作——增

append：追加一条数据到列表的最后

name = ["Zhangsan","XiongDa","Lisi"]
name.append("wangwu")
print name
输出结果：
[‘Zhangsan‘, ‘XiongDa‘, ‘Lisi‘, ‘wangwu‘]

insert：指定位置插入一条数据

name = ["Zhangsan","XiongDa","Lisi"]
name.insert(1,"wangwu")    #在下标为1的位置插入一条数据“wangwu”
print name
输出结果：
[‘Zhangsan‘, ‘wangwu‘, ‘XiongDa‘, ‘Lisi‘]

python列表操作——删

name = ["Zhangsan","XiongDa","Lisi"]
name.remove("Lisi")    #删除指定的数据
print name
输出结果：
[‘Zhangsan‘, ‘XiongDa‘]

name = ["Zhangsan","XiongDa","Lisi"]
del name[0]    #删掉下标为0的一条数据
print name
输出结果：
[‘XiongDa‘, ‘Lisi‘]

name = ["Zhangsan","XiongDa","Lisi"]
name.pop()    #删除最后一条数据
print name
输出结果：
[‘Zhangsan‘, ‘XiongDa‘]

如果当pop()中带入了参数，其效果等同于del

Name.pop(1) == del name[1]

python列表操作——改

name = ["Zhangsan","XiongDa","Lisi"]
name[1] = "wangwu"
print name
输出结果：
[‘Zhangsan‘, ‘wangwu‘, ‘Lisi‘]

python列表操作——查

name = ["Zhangsan","XiongDa","Lisi","wangwu"]
print(name[1])     #直接取出下标为1的数据
输出结果：
XiongDa

name = ["Zhangsan","XiongDa","Lisi","wangwu"]
print(name[0:2])   #取出从下标0到下标1的数据，不包括2（顾头不顾尾）
输出结果：
[‘Zhangsan‘, ‘XiongDa‘]

当下标为负数时，则从右边开始取

name = ["Zhangsan","XiongDa","Lisi","wangwu"]
print(name[-1])     #直接取出下标为1的数据
输出结果：
wangwu

name = ["Zhangsan","XiongDa","Lisi","wangwu"]
print(name[-3:-1])   #从倒数第三个开始取，取到倒数第二个，因为不包括-1
输出结果：
[‘XiongDa‘, ‘Lisi‘]

name = ["Zhangsan","XiongDa","Lisi","wangwu"]
print(name[-3:])   #从倒数第三个开始取，取到倒数第一个
输出结果：
[‘XiongDa‘, ‘Lisi‘, ‘wangwu‘]
同理从昨天开始取时
name[0:3] == name[:3]

列表其他操作：

name = ["Zhangsan","XiongDa","Lisi","wangwu","Lisi"]
name.count("Lisi")  #统计Lisi出现的次数
name.clear()         #清空数据
name.reverse()       #反转列表
name.sort()           正向排序
name2 = ["1","2"]
name.extend(name2)  #两个数组合并，name2放在后面