Python 基础 - Day 2 Learning Note - Dictionary 字典

Posted 2020-09-26

 

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