Python – Convert Snake Case String to Camel Case

Given a snake case string, convert to camel case.

Input : test_str = ‘geeksforgeeks_is_best_for_geeks’ 
Output : geeksforgeeksIsBestForGeeks 
Explanation : String converted to Camel Case.

Input : test_str = ‘geeksforgeeks_best_for_geeks’ 
Output : geeksforgeeksBestForGeeks 
Explanation : String converted to Camel Case. 

Method #1 : Using split() + join() + title() + generator expression

The combination of above functions can be used to solve this problem. In this, we first split all underscores, and then join the string appending initial word, followed by title cased words using generator expression and title().

Python3

# Python3 code to demonstrate working of
# Convert Snake Case String to Camel Case
# Using split() + join() + title() + generator expression

# initializing string
test_str = 'geeksforgeeks_is_best'

# printing original string
print("The original string is : " + str(test_str))

# split underscore using split
temp = test_str.split('_')

# joining result
res = temp[0] + ''.join(ele.title() for ele in temp[1:])

# printing result
print("The camel case string is : " + str(res))

Output

The original string is : geeksforgeeks_is_best
The camel case string is : geeksforgeeksIsBest

Method #2  : Using  split() + join() + title() + map()

The combination of above functions can be used to solve this problem. In this, we perform the task of extending logic to entire strings using map(). 

Python3

# Python3 code to demonstrate working of
# Convert Snake Case String to Camel Case
# Using split() + join() + title() + map()

# initializing string
test_str = 'geeksforgeeks_is_best'

# printing original string
print("The original string is : " + str(test_str))

# saving first and rest using split()
init, *temp = test_str.split('_')

# using map() to get all words other than 1st
# and titlecasing them
res = ''.join([init.lower(), *map(str.title, temp)])

# printing result
print("The camel case string is : " + str(res))

Output

The original string is : geeksforgeeks_is_best
The camel case string is : geeksforgeeksIsBest