how to replace a column with another column in pandas code example

Example 1: replace column values pandas

df['column'] = df['column'].str.replace(',','-')
df

Example 2: replace one row with another in python

df.loc[(df.Event == 'Dance'),'Event']='Hip-Hop'
df

Example 3: replace value of dataframe with another column

df['col1'] = np.where(df['col1'] == 0, df['col2'], df['col1'])
df['col1'] = np.where(df['col1'] == 0, df['col3'], df['col1'])

Example 4: replace 3 column with another column pandas

df['B'] = df1['E']