Skip to content
Related Articles
Python | Summation of integers in heterogenous list
• Last Updated : 27 Aug, 2019

Sometimes, while working with Python, we can come across a problem in which we require to find the sum of list. This problem is easier to solve. But this can get complex in case we have mixture of data types to go along with it. Let’s discuss certain ways in which this task can be performed.

Method #1 : Using Type casting + Exception Handling
We can employ a brute force method to type caste each element and catch the exception if any occurs. This can ensure that only integers are added to sum and hence can solve the problem.

 `# Python3 code to demonstrate working of``# Summation of integers in heterogenous list``# using type caste and exception handling`` ` `# initializing list``test_list ``=` `[``5``, ``6``, ``"gfg"``, ``8``, (``5``, ``7``), ``'is'``, ``9``]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# Summation of integers in heterogenous list``# using type caste and exception handling``res ``=` `0``for` `ele ``in` `test_list:``    ``try``:``        ``res ``+``=` `int``(ele)``    ``except` `:``        ``pass`` ` `# printing result ``print``(``"Summation of integers in list : "` `+` `str``(res))`
Output :
```The original list is : [5, 6, 'gfg', 8, (5, 7), 'is', 9]
Summation of integers in list : 28
```

Method #2 : Using `sum() + isinstance()`
This problem can also be solved using the inbuilt function of `sum()` and it also supports the instance filter using `isinstance()` which can be feeded with integer and hence solve the problem.

 `# Python3 code to demonstrate working of``# Summation of integers in heterogenous list``# using sum() + isinstance()`` ` `# initializing list``test_list ``=` `[``5``, ``6``, ``"gfg"``, ``8``, (``5``, ``7``), ``'is'``, ``9``]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# Summation of integers in heterogenous list``# using sum() + isinstance()``res ``=` `sum``(``filter``(``lambda` `i: ``isinstance``(i, ``int``), test_list))`` ` `# printing result ``print``(``"Summation of integers in list : "` `+` `str``(res))`
Output :
```The original list is : [5, 6, 'gfg', 8, (5, 7), 'is', 9]
Summation of integers in list : 28
```

Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning – Basic Level Course

My Personal Notes arrow_drop_up