Introduction to Merging/Concatenating DataFrames

This section introduces the concept of merging/concatenating DataFrames in Pandas.

Concept

Till now, you’ve been dealing with a single DataFrame object. Often, there you may need to combine multiple datasets into one object, based on a common column.

Syntax

Assuming you have two DataFrame objects, df1 and df2, the most basic type of merge can be done with the following syntax:

merged = pd.merge(df1, df2)

Multiple options exist in the merge; you could do a Left/Right/Outer join, or choose the columns to perform the merge.

There are also other ways to combine DataFrame objects, such as by using .join() or .append().

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