访问数据
Python 金融进阶
Kennedy Behrman
Data Engineer, Author, Founder
账户余额
课程数据介绍
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| b | AAD | 1234nmk | 390789.11 |
| c | BA | mm3d90 | 13.02 |
accounts
用方括号访问列
accounts['Balance']
用方括号访问列
accounts['Balance']
| a | 1222.00 |
| b | 390789.11 |
| c | 13.02 |
Name: Balance, dtype: float6
用点语法访问列
accounts.Balance
| Balance | |
|---|---|
| a | 1222.00 |
| b | 390789.11 |
| c | 13.02 |
访问多个列
accounts[['Bank Code', 'Account#']]
访问多个列
accounts[['Bank Code', 'Account#']]
| Bank Code | Account# | |
|---|---|---|
| a | BA | ajfdk2 |
| b | AAD | 1234nmk |
| c | BA | mm3d90 |
用方括号访问行
accounts[0:2]
用方括号访问行
accounts[0:2]
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| b | AAD | 1234nmk | 390789.11 |
用方括号访问行
accounts[[True, False, True]]
用方括号访问行
accounts[[True, False, True]]
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| c | BA | mm3d90 | 13.02 |
loc 与 iloc
loc按名称访问iloc按位置访问
loc
accounts.loc['b']
| Bank Code | AAD |
| Account# | 1234nmk |
| Balance | 390789 |
Name: b, dtype: object
loc
accounts.loc[['a','c']]
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| c | BA | mm3d90 | 13.02 |
df.loc[[True, False, True]]
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| c | BA | mm3d90 | 13.02 |
用 loc 选列
accounts.loc['a':'c','Balance']
accounts.loc['a':'c', ['Balance','Account#']]
accounts.loc['a':'c',[True,False,True]]
accounts.loc['a':'c','Bank Code':'Balance']
用 loc 选列
accounts.loc['a':'c',['Bank Code', 'Balance']]
用 loc 选列
accounts.loc['a':'c',['Bank Code', 'Balance']]
| Bank Code | Balance | |
|---|---|---|
| a | BA | 1222.00 |
| b | AAD | 390789.11 |
| c | BA | 13.02 |
iloc
accounts.iloc[0:2, [0,2]]
iloc
accounts.iloc[0:2, [0,2]]
iloc
accounts.iloc[0:2, [0,2]]
| Bank Code | Balance | |
|---|---|---|
| a | BA | 1222.00 |
| b | AAD | 390789.11 |
设置单个值
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| b | AAD | 1234nmk | 390789.11 |
| c | BA | mm3d90 | 13.02 |
accounts.loc['a', 'Balance'] = 0
设置单个值
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 0.00 |
| b | AAD | 1234nmk | 390789.11 |
| c | BA | mm3d90 | 13.02 |
accounts.loc['a', 'Balance'] = 0
设置多个值
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| b | AAD | 1234nmk | 390789.11 |
| c | BA | mm3d90 | 13.02 |
accounts.iloc[:2, 1:] = 'NA'
设置多列
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | NA | NA |
| b | AAD | NA | NA |
| c | BA | mm3d90 | 13.02 |
accounts.iloc[:2, 1:] = 'NA'
¡Vamos a practicar!
Python 金融进阶
