[Python Cookbook] Pandas: Indexing of DataFrame

Posted 2021-02-08 Sherrrry

Selecting a Row

df.loc[index] # if index is a string, add ‘ ‘; if index is a number, no ‘ ‘

or

df.iloc[row_num]

 

Selecting a Column

df[‘col_name‘]

Or

df.col_name

 

Selecting an Element

df.loc[index, ‘col_name‘]

Selecting Multiple Discontinuous Rows

df.loc[[row_num1, row_num2, ...]] # can‘t use df.iloc here

Or 

df.loc[bool_expr]

 E.g.

nyc[nyc.cand_nm.isin(df11 p.cand nm)]
nyc[nyc.cand_nm.isnull()]
nyc[nyc.cand_nm.isnull()]
nyc[nyc.contb_receipt_amt >0]