How to merge rows in Pandas DataFrame using concat()? pandas合并行

How to merge rows in Pandas DataFrame using concat()?For merging rows in Pandas, you can use the concat function. Here is an example:

import pandas as pd

# create two dataframes
df1 = pd.DataFrame({'Col1': ['A', 'B', 'C'], 'Col2': [1, 2, 3]})
df2 = pd.DataFrame({'Col1': ['D', 'E', 'F'], 'Col2': [4, 5, 6]})

# concatenate the rows
result = pd.concat([df1, df2])

# print the result
print(result)

This will output a new DataFrame with 6 rows, where the rows from df2 are appended to the rows of df1. You can use the axis parameter to control whether the concatenation is done row-wise or column-wise. If axis=0 (default), rows are merged vertically (appended) whereas axis=1 merges horizontally (side by side).