Python enumerate() 函数如何实现索引功能
作者:杨枫哥
这篇文章主要介绍了Python enumerate() 函数如何实现索引功能,文中通过示例代码介绍的非常详细,对大家的学习或者工作具有一定的参考学习价值,需要的朋友可以参考下
1.描述:
enumerate()函数用于将一个可遍历的数据对象(如列表,元组,字符串)组合为一个索引序列,同时列出数据和数据索引(下标),一般用于for循环当中
2.语法
enumerate(sequence, [start=0])
3.参数:
- sequence:一个序列,迭代器或其他支持迭代对象
- start:可选参数,下标起始位置,默认从索引0开始
4.返回值
返回enumerate(枚举)对象
5.实例
list1 = [10,20,30,40,"maple","yf",60] tup1 = (100,200,300,400,"hao","qazert",600) str1 = "1234qwertjdsa22323" for index1,item1 in enumerate(list1): print("index1 = %d, item1 = %s" %(index1,item1,)) print("------------------------------") for index2, item2 in enumerate(list1,start = 2): print("index2 = %d, item2 = %s" %(index2,item2,)) print("******************************") for index3,item3 in enumerate(tup1): print("index3 = %d, item3 = %s" % (index3, item3,)) print("==============================") for index4,item4 in enumerate(tup1, start = 4): print("index4 = %d, item4 = %s" % (index4, item4,)) print("%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%") for index5,item5 in enumerate(str1): print("index4 = %d, item4 = %s" % (index5, item5,)) print("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$") for index6,item6 in enumerate(str1,start = 6): print("index4 = %d, item4 = %s" % (index6, item6,)) #输出的结果如下: index1 = 0, item1 = 10 index1 = 1, item1 = 20 index1 = 2, item1 = 30 index1 = 3, item1 = 40 index1 = 4, item1 = maple index1 = 5, item1 = yf index1 = 6, item1 = 60 ------------------------------ index2 = 2, item2 = 10 index2 = 3, item2 = 20 index2 = 4, item2 = 30 index2 = 5, item2 = 40 index2 = 6, item2 = maple index2 = 7, item2 = yf index2 = 8, item2 = 60 ****************************** index3 = 0, item3 = 100 index3 = 1, item3 = 200 index3 = 2, item3 = 300 index3 = 3, item3 = 400 index3 = 4, item3 = hao index3 = 5, item3 = qazert index3 = 6, item3 = 600 ============================== index4 = 4, item4 = 100 index4 = 5, item4 = 200 index4 = 6, item4 = 300 index4 = 7, item4 = 400 index4 = 8, item4 = hao index4 = 9, item4 = qazert index4 = 10, item4 = 600 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% index4 = 0, item4 = 1 index4 = 1, item4 = 2 index4 = 2, item4 = 3 index4 = 3, item4 = 4 index4 = 4, item4 = q index4 = 5, item4 = w index4 = 6, item4 = e index4 = 7, item4 = r index4 = 8, item4 = t index4 = 9, item4 = j index4 = 10, item4 = d index4 = 11, item4 = s index4 = 12, item4 = a index4 = 13, item4 = 2 index4 = 14, item4 = 2 index4 = 15, item4 = 3 index4 = 16, item4 = 2 index4 = 17, item4 = 3 $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ index4 = 6, item4 = 1 index4 = 7, item4 = 2 index4 = 8, item4 = 3 index4 = 9, item4 = 4 index4 = 10, item4 = q index4 = 11, item4 = w index4 = 12, item4 = e index4 = 13, item4 = r index4 = 14, item4 = t index4 = 15, item4 = j index4 = 16, item4 = d index4 = 17, item4 = s index4 = 18, item4 = a index4 = 19, item4 = 2 index4 = 20, item4 = 2 index4 = 21, item4 = 3 index4 = 22, item4 = 2 index4 = 23, item4 = 3
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。