Question

I have a list like this:

a = ['1 MB', '2 MB']

I want to sum all the elements in a.

I figured I first have to create integer list and use sum() function. How can I do that?

Answer 1

Use the built-in split to separate the number from the rest of the string

>>> a = ['1 MB', '2 MB']
>>> sum([int(s.split(' ')[0]) for s in a])
3

s.split(' ') creates the list ['1', 'MB']

Or use a generator expression to avoid the unneeded list that the list comprehension creates:

>>> a = ['1 MB', '2 MB']
>>> sum(int(s.split(' ')[0]) for s in a)
3