python常用的数据类型包含6种:
1、Number(数字)
2、String(字符串)
3、List(列表)
4、Tuple(元组)
5、Set(集合)
6、Dictionary(字典)
一、Number(数字)
包括int,float,bool(python3),complex(负数)几种类型
二、List(列表)
list是有序的对象集合,索引值以0为开始值,-1为从末尾的开始位置。
主要操作功能如下:
#通过下标访问列表的值list1 = ["chk","ldlk",1,2,"sdfkj"]for i in range(len(list1)): print("%s" % list1[i])#切片print(list1[1:-1])#追加list1.append("jjjjjjj")print("追加",list1)#指定位置插入list1.insert(1,"1111111")print("指定位置插入",list1)#移除list1.remove(2)print(list1)#输出最后一个值print(list1.pop())#连接,将list转化为字符串list1 = ["chk","ldlk","lkvl","lkdjsflk","sdfkj"]sr = " ".join(list1)print(type(sr))#查找索引下标#1、这种只能查到相同元素的第一个元素对应的索引下标print(list1.index("sdfkj"))#2、利用enumerate函数与普通for循环对比。for i in range(len(list1)): print("索引:"+str(i),",值"+list1[i])for index,value in enumerate(list1): print("索引:"+str(index),", 值:"+value)#排序list2 = [9,3,4,2,45]list2.sort()print("排序后",list2)list3 = ["s","d","f","r","l"]list3.sort()print("排序后",list3)#反转list2.reverse()print("反转后",list2)list3.reverse()print("反转后",list3)#相加list = list2 + list3print("两个列表相加list",list)#清除list.clear()print("clear清除后list",list)
list可以转化为字符串
小例子:
list1 = ["chk","ldlk","lkvl","lkdjsflk","sdfkj"]sr = " ".join(list1)print(type(sr))如果被转化的list中包含数字,会报错“error: sequence item 2: expected str instance, int found”,list包含数字不能直接转化为字符串解决办法:print(" ".join('%s' %id for id in list1))
list1 = ["chk","ldlk",1,2,"sdfkj"]sr1 = " ".join('%s' %id for id in list1)print(sr1,type(sr1))