Let’s understand how we can concatenate two or more Data Frames. A concatenation of two or more data frames can be done using pandas.concat() method. concat() in pandas works by combining Data Frames across rows or columns. We can concat two or more data frames either along rows (axis=0) or along columns (axis=1)
Creating Dataframe to Concatenate Two or More Pandas DataFrames
Create two Data Frames which we will be concatenating now. For creating Data frames we will be using numpy and pandas.
Python3
import pandas as pdimport numpy as npdf1 = pd.DataFrame(np.random.randint(25, size=(4, 4)), index=["1", "2", "3", "4"], columns=["A", "B", "C", "D"])df2 = pd.DataFrame(np.random.randint(25, size=(6, 4)), index=["5", "6", "7", "8", "9", "10"], columns=["A", "B", "C", "D"])df3 = pd.DataFrame(np.random.randint(25, size=(4, 4)), columns=["A", "B", "C", "D"])df4 = pd.DataFrame(np.random.randint(25, size=(4, 4)), columns=["E", "F", "G", "H"])display(df1, df2, df3, df4) |
Output:
DataFrame with some random data for testing
Concatenate Two or More Pandas DataFrames
We’ll pass two dataframes to pd.concat() method in the form of a list and mention in which axis you want to concat, i.e. axis=0 to concat along rows, axis=1 to concat along columns.
Python3
# concatenating df1 and df2 along rowsvertical_concat = pd.concat([df1, df2], axis=0)# concatenating df3 and df4 along columnshorizontal_concat = pd.concat([df3, df4], axis=1)display(vertical_concat, horizontal_concat) |
Output:
Output DataFrame for different axis parameter values
