Pandas insert method allows the user to insert a column in a dataframe or series(1-D Data frame). A column can also be inserted manually in a data frame by the following method, but there isn’t much freedom here.
For example, even column location can’t be decided and hence the inserted column is always inserted in the last position.
Syntax:
DataFrameName.insert(loc, column, value, allow_duplicates = False)
Parameters:
loc: loc is an integer which is the location of column where we want to insert new column. This will shift the existing column at that position to the right.
column: column is a string which is name of column to be inserted.
value: value is simply the value to be inserted. It can be int, string, float or anything or even series / List of values. Providing only one value will set the same value for all rows.
allow_duplicates : allow_duplicates is a boolean value which checks if column with same name already exists or not.
Find the link to csv file used from here.
Inserting a column with static value:
Python3
# importing pandas moduleimport pandas as pd # reading csv filedata = pd.read_csv("pokemon.csv") # displaying dataframe - Output 1data.head() |
Output:
After Inserting column:
Python3
# importing pandas moduleimport pandas as pd# reading csv filedata = pd.read_csv("pokemon.csv")# displaying dataframe - Output 1data.head()# inserting column with static value in data framedata.insert(2, "Team", "Any")# displaying data frame again - Output 2data.head() |
Passing series with different value for each row:
In this example, a series is created and some values are passed to the series through a for loop. After that, the series is passed in pandas insert function to append series in the Data frame with values passed.
Python
# importing pandas moduleimport pandas as pd# creating a blank seriesType_new = pd.Series([])# reading csv filedata = pd.read_csv("pokemon.csv")# running a for loop and assigning some values to seriesfor i in range(len(data)): if data["Type"][i] == "Grass": Type_new[i]="Green" elif data["Type"][i] == "Fire": Type_new[i]="Orange" elif data["Type"][i] == "Water": Type_new[i]="Blue" else: Type_new[i]= data["Type"][i] # inserting new column with values of list made above data.insert(2, "Type New", Type_new)# list outputdata.head() |
Output:
