Pandas: Update null elements with value in the same location in other
Pandas Joining and merging DataFrame: Exercise-15 with Solution
Write a Pandas program to Combine two DataFrame objects by filling null values in one DataFrame with non-null values from other DataFrame.
Test Data:
Original DataFrames: A B 0 NaN 3 1 0.0 4 2 NaN 5
A B 0 1 3.0 1 1 NaN 2 3 3.0
Sample Solution:
Python Code :
import pandas as pd
df1 = pd.DataFrame({'A': [None, 0, None], 'B': [3, 4, 5]})
df2 = pd.DataFrame({'A': [1, 1, 3], 'B': [3, None, 3]})
df1.combine_first(df2)
print("Original DataFrames:")
print(df1)
print("--------------------")
print(df2)
print("\nMerge two dataframes with different columns:")
result = df1.combine_first(df2)
print(result)
Sample Output:
Original DataFrames: A B 0 NaN 3 1 0.0 4 2 NaN 5 -------------------- A B 0 1 3.0 1 1 NaN 2 3 3.0 Merge two dataframes with different columns: A B 0 1.0 3 1 0.0 4 2 3.0 5
Python Code Editor:
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Previous: Write a Pandas program to merge two given dataframes with different columns.
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