You can use the following syntax to subtract one pandas DataFrame from another:
df1.subtract(df2)
If you have a character column in each DataFrame, you may first need to move it to the index column of each DataFrame:
df1.set_index('char_column').subtract(df2.set_index('char_column'))
The following examples show how to use each syntax in practice.
Example 1: Subtract Two Pandas DataFrames (Numerical Columns Only)
Suppose we have the following two pandas DataFrames that only have numerical columns:
import pandas as pd #create first DataFrame df1 = pd.DataFrame({'points': [5, 17, 7, 19, 12, 13, 9, 24], 'assists': [4, 7, 7, 6, 8, 7, 10, 11]}) print(df1) points assists 0 5 4 1 17 7 2 7 7 3 19 6 4 12 8 5 13 7 6 9 10 7 24 11 #create second DataFrame df2 = pd.DataFrame({'points': [4, 22, 10, 3, 7, 8, 12, 10], 'assists': [3, 5, 5, 4, 7, 14, 9, 5]}) print(df2) points assists 0 4 3 1 22 5 2 10 5 3 3 4 4 7 7 5 8 14 6 12 9 7 10 5
The following code shows how to subtract the corresponding values between the two DataFrames:
#subtract corresponding values between the two DataFrames
df1.subtract(df2)
points assists
0 1 1
1 -5 2
2 -3 2
3 16 2
4 5 1
5 5 -7
6 -3 1
7 14 6
Example 2: Subtract Two Pandas DataFrames (Mix of Character & Numerical Columns)
Suppose we have the following two pandas DataFrames that each have a character column called team:
import pandas as pd #create first DataFrame df1 = pd.DataFrame({'team': ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H'], 'points': [5, 17, 7, 19, 12, 13, 9, 24], 'assists': [4, 7, 7, 6, 8, 7, 10, 11]}) print(df1) team points assists 0 A 5 4 1 B 17 7 2 C 7 7 3 D 19 6 4 E 12 8 5 F 13 7 6 G 9 10 7 H 24 11 #create second DataFrame df2 = pd.DataFrame({'team': ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H'], 'points': [4, 22, 10, 3, 7, 8, 12, 10], 'assists': [3, 5, 5, 4, 7, 14, 9, 3]}) print(df2) team points assists 0 A 4 3 1 B 22 5 2 C 10 5 3 D 3 4 4 E 7 7 5 F 8 14 6 G 12 9 7 H 10 3
The following code shows how to move the team column to the index column of each DataFrame and then subtract the corresponding values between the two DataFrames:
#move 'team' column to index of each DataFrame and subtract corresponding values
df1.set_index('team').subtract(df2.set_index('team'))
points assists
team
A 1 1
B -5 2
C -3 2
D 16 2
E 5 1
F 5 -7
G -3 1
H 14 8
Additional Resources
The following tutorials explain how to perform other common tasks in pandas:
Pandas: How to Find the Difference Between Two Columns
Pandas: How to Find the Difference Between Two Rows
Pandas: How to Subtract Two Columns