python introductory tutorial list operations
python list operation - add
append: Append a piece of data to the end of the list
name = ["Zhangsan","XiongDa","Lisi"] name.append("wangwu")print name 输出结果: ['Zhangsan', 'XiongDa', 'Lisi', 'wangwu']
insert: Insert a piece of data at the specified position
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']
pythonList operation - delete
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']
If parameters are brought into pop(), the effect will be the same In del
Name.pop(1) == del name[1]
##pythonList operations—— Change
name = ["Zhangsan","XiongDa","Lisi"] name[1] = "wangwu"print name 输出结果: ['Zhangsan', 'wangwu', 'Lisi']
##pythonList operation - check
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']
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]
List of other operations:
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
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