pythondict排序原理
Python标准库使用OrderedDict类的实例讲解目标:创建一个字典,记录几对python词语,使用OrderedDict类来写,并按顺序输出。
写完报错:
|
[root@centos7 tmp] # python python_terms.py File "python_terms.py" , line 9 from name,language in python_terms.items(): ^ SyntaxError: invalid syntax |
代码如下:
|
from collections import OrderedDict python_terms = OrderedDict() python_terms[ 'key' ] = 'vlaue' python_terms[ 'if' ] = 'match' python_terms[ 'from' ] = 'import' from name,language in python_terms.items(): print ( "python have many terms " + name.title() + language.title() + '.' ) ~ |
结果for循环的for写成from了……总是出现简单的错误。
最终,正确代码如下:
|
from collections import OrderedDict python_terms = OrderedDict() python_terms[ 'key' ] = 'vlaue' python_terms[ 'if' ] = 'match' python_terms[ 'from' ] = 'import' for name,language in python_terms.items(): print ( "python have many terms " + name.title() + " " + language.title() + '.' ) |
第一行,从模块collections中导入OrderedDict类;
第二行,创建了OrderedDict类的一个实例,并将其存储到python_terms中,也就是创建了一个空字典;
第三至五行,为字典添加键值对;
最后,循环输出结果。
运行结果:
|
[root@centos7 tmp] # python python_terms.py python have many terms Key Vlaue. python have many terms If Match. python have many terms From Import. |
总结
以上就是这篇文章的全部内容了,希望本文的内容对大家的学习或者工作具有一定的参考学习价值,谢谢大家对开心学习网的支持。如果你想了解更多相关内容请查看下面相关链接
原文链接:https://blog.csdn.net/zsx0728/article/details/81234532