データへアクセス
Intermediate Python for Finance
Kennedy Behrman
Data Engineer, Author, Founder
口座残高
レッスン用データの紹介
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| b | AAD | 1234nmk | 390789.11 |
| c | BA | mm3d90 | 13.02 |
accounts
ブラケットで列にアクセス
accounts['Balance']
ブラケットで列にアクセス
accounts['Balance']
| a | 1222.00 |
| b | 390789.11 |
| c | 13.02 |
Name: Balance, dtype: float6
ドット記法で列にアクセス
accounts.Balance
| Balance | |
|---|---|
| a | 1222.00 |
| b | 390789.11 |
| c | 13.02 |
複数列にアクセス
accounts[['Bank Code', 'Account#']]
複数列にアクセス
accounts[['Bank Code', 'Account#']]
| Bank Code | Account# | |
|---|---|---|
| a | BA | ajfdk2 |
| b | AAD | 1234nmk |
| c | BA | mm3d90 |
ブラケットで行にアクセス
accounts[0:2]
ブラケットで行にアクセス
accounts[0:2]
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| b | AAD | 1234nmk | 390789.11 |
ブラケットで行にアクセス
accounts[[True, False, True]]
ブラケットで行にアクセス
accounts[[True, False, True]]
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| c | BA | mm3d90 | 13.02 |
loc と iloc
locは名前でアクセスilocは位置でアクセス
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 |
loc で列を選択
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']
loc で列を選択
accounts.loc['a':'c',['Bank Code', 'Balance']]
loc で列を選択
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 |
単一値の設定
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| b | AAD | 1234nmk | 390789.11 |
| c | BA | mm3d90 | 13.02 |
accounts.loc['a', 'Balance'] = 0
単一値の設定
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 0.00 |
| b | AAD | 1234nmk | 390789.11 |
| c | BA | mm3d90 | 13.02 |
accounts.loc['a', 'Balance'] = 0
複数値の設定
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | ajfdk2 | 1222.00 |
| b | AAD | 1234nmk | 390789.11 |
| c | BA | mm3d90 | 13.02 |
accounts.iloc[:2, 1:] = 'NA'
複数列の設定
| Bank Code | Account# | Balance | |
|---|---|---|---|
| a | BA | NA | NA |
| b | AAD | NA | NA |
| c | BA | mm3d90 | 13.02 |
accounts.iloc[:2, 1:] = 'NA'
演習に進みましょう！
Intermediate Python for Finance
