how to plot two columns of dataframe in python code example

Example 1: plotting two columns of a dataframe in python

df.plot(x='col_name_1', y='col_name_2', style='o')

Example 2: pandas merge two columns from different dataframes

#suppose you have two dataframes df1 and df2, and 
#you need to merge them along the column id
df_merge_col = pd.merge(df1, df2, on='id')

Example 3: how to merge two pandas dataframes on a column

import pandas as pd
T1 = pd.merge(T1, T2, on=T1.index, how='outer')

Example 4: merge two columns pandas

df["period"] = df["Year"] + df["quarter"]