码迷,mamicode.com
首页 > 编程语言 > 详细

Python 基础 - Day 2 Learning Note - Dictionary 字典

时间:2017-07-01 22:37:23      阅读:157      评论:0      收藏:0      [点我收藏+]

标签:alt   dict   learning   python   lte   nan   span   balance   嵌套   

 

Dictionary的表达式:{KEY: VALUE} 

  • value 可以是string, list, or disctionary.  层层嵌套,e.g 多层菜单
  • Dictionary的打印结果是无序的。因为可以通过key来查找value内容,所有不用像list一样,通过下标来查找。
  • key必须是唯一的,天生去重复。
Dataset = {
    Equity Fund: Deep value,
    Balanced Fund: Market oriented with a growth bias,
    Fixed Income Fund: [Government bond,Financial Notes,Credit Bond,MBS],
}
print(Dataset)

{‘Equity Fund‘: ‘Deep value‘, ‘Balanced Fund‘: ‘Market oriented with a growth bias‘, ‘Fixed Income Fund‘: [‘Government bond‘, ‘Financial Notes‘, ‘Credit Bond‘, ‘MBS‘]}

添加

Dataset["Alternative Investment"] = ‘REITS‘  # 添加Key
print(Dataset)

{‘Equity Fund‘: ‘Deep value‘, ‘Balanced Fund‘: ‘Market oriented with a growth bias‘, ‘Fixed Income Fund‘: [‘Government bond‘, ‘Financial Notes‘, ‘Credit Bond‘, ‘MBS‘], ‘Alternative Investment‘: ‘REITS‘}

修改

Dataset["Equity Fund"] = Fundamental Growth
Dataset[‘Fixed Income Fund‘][1] = ‘MTN‘
print(Dataset)

{‘Equity Fund‘: ‘Fundamental Growth‘, ‘Balanced Fund‘: ‘Market oriented with a growth bias‘, ‘Fixed Income Fund‘: [‘Government bond‘, ‘MTN‘, ‘Credit Bond‘, ‘MBS‘], ‘Alternative Investment‘: ‘REITS‘}

删除

del Dataset[Equity Fund]
print(Dataset)

or 

Dataset.pop("Equity Fund") 
print(Dataset)

or 随机删除

Dataset.popitem()

 

查找

 

Python 基础 - Day 2 Learning Note - Dictionary 字典

标签:alt   dict   learning   python   lte   nan   span   balance   嵌套   

原文地址:http://www.cnblogs.com/lg100lg100/p/7082239.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!