6.5. DataFrame Getitem

6.5.1. SetUp

>>> import pandas as pd
>>>
>>> df = pd.DataFrame([
...     {'firstname': 'Alice', 'lastname': 'Apricot', 'age': 30},
...     {'firstname': 'Bob', 'lastname': 'Blackthorn', 'age': 31},
...     {'firstname': 'Carol', 'lastname': 'Corn', 'age': 32},
... ], index=['a', 'b', 'c'])

>>> df
  firstname    lastname  age
a     Alice     Apricot   30
b       Bob  Blackthorn   31
c     Carol        Corn   32

6.5.2. Column Getitem

  • df['column_name'] - get column by label

  • Works for any column name

>>> df['firstname']
a    Alice
b      Bob
c    Carol
Name: firstname, dtype: str

6.5.3. Column Loc

  • df.loc[:, 'column_name'] - get column by label

  • Works for any column name

>>> df.loc[:, 'firstname']
a    Alice
b      Bob
c    Carol
Name: firstname, dtype: str

6.5.4. Column Attribute

  • DataFrame.column_name - get column by attribute

  • Not recommended

  • Works only if column name is a valid Python identifier and does not conflict with existing DataFrame methods or attributes

>>> df.firstname
a    Alice
b      Bob
c    Carol
Name: firstname, dtype: str

6.5.5. Assignments