How do I sum the first value in each tuple in a list of tuples in Python?

Abstraction: Pythonic ways to sum a specific index across a list of tuples

Key points:

• Naive approach: iterate with for pair in list: sum += pair[0]
• Idiomatic solution: sum(pair[0] for pair in list_of_pairs) uses a generator expression
• Alternative with zip: sum(zip(*list_of_pairs)[0]) unpacks and selects the first column
• Generator expression avoids building an intermediate list, preferred for large datasets

Connections: Stackoverflow · Python Programming

Source: http://stackoverflow.com/questions/638048/how-do-i-sum-the-first-value-in-each-tuple-in-a-list-of-tuples-in-python