How to Get First Column of Pandas DataFrame (With Examples)


You can use the following syntax to get the first column of a pandas DataFrame:

df.iloc[:, 0]

The result is a pandas Series. If you’d like the result to be a pandas DataFrame instead, you can use the following syntax:

df.iloc[:, :1]

The following examples show how to use this syntax in practice.

Example 1: Get First Column of Pandas DataFrame (Return a Series)

The following code shows how to get the first column of a pandas DataFrame:

import pandas as pd

#create DataFrame
df = pd.DataFrame({'points': [25, 12, 15, 14, 19, 23, 25, 29],
                   'assists': [5, 7, 7, 9, 12, 9, 9, 4],
                   'rebounds': [11, 8, 10, 6, 6, 5, 9, 12]})

#view DataFrame
print(df)

   points  assists  rebounds
0      25        5        11
1      12        7         8
2      15        7        10
3      14        9         6
4      19       12         6
5      23        9         5
6      25        9         9
7      29        4        12

#get first column
first_col = df.iloc[:, 0]

#view first column
print(first_col)

0    25
1    12
2    15
3    14
4    19
5    23
6    25
7    29
Name: points, dtype: int64

The result is a pandas Series:

#check type of first_col
print(type(first_col))

<class 'pandas.core.series.Series'>

Example 2: Get First Column of Pandas DataFrame (Return a DataFrame)

The following code shows how to get the first column of a pandas DataFrame and return a DataFrame as a result:

#get first column (and return a DataFrame)
first_col = df.iloc[:, :1]

#view first column
print(first_col)

   points
0      25
1      12
2      15
3      14
4      19
5      23
6      25
7      29

#check type of first_col
print(type(first_col))

<class 'pandas.core.frame.DataFrame'>

Additional Resources

How to Add a Column to a Pandas DataFrame
How to Insert a Column Into a Pandas DataFrame
How to Create a New Column Based on a Condition in Pandas

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