how to insert a column in pandas dataframe code example

Example 1: pandas insert column in the beginning

insert_index = 0
insert_colname = 'new column'
insert_values = [1, 2, 3, 4, 5] # this can be a numpy array too
df.insert(loc=insert_index, column=insert_colname, value=insert_values)

Example 2: how to add a column to a pandas df

#using the insert function:
df.insert(location, column_name, list_of_values) 
#example
df.insert(0, 'new_column', ['a','b','c'])
#explanation:
#put "new_column" as first column of the dataframe
#and puts 'a','b' and 'c' as values

#using array-like access:
df['new_column_name'] = value

#df stands for dataframe

Example 3: insert new column to dataframe

group = np.random.randint(10, size=6)
df_new['Group'] = group