How to sum values in dictionary with multiple elements in string?

Question

I'm trying to sum values in a dictionary that has strings for keys, and lists as the values.

The standard sum(d.values()) doesn't work.

d= {'a': [6,7,8], 'b':[30,-3, 5000,] 'c':[200.6], 'd':[2,2,2,2,2,2,2]}

When I use the sum(d.values()) I get:

TypeError: unsupported operand type(s) for +: 'int' and 'list'

Answer 1

You can use sum and map on the dicts's values like this

>>> sum(map(sum, d.values()))
5262.6

Answer 2

The best way is to create a generator that takes the sum of each array, and fianlly finds the sum of the values in the generator.

or if you just want to see the code.

sum(sum(a) for a in d.values())

Answer 3

You can unpack the list of lists returned by d.values() as in this question.

sum(y for x in d.values() for y in x)

Answer 4

You can do a sum() of the sum() of each sublist:

sum(sum(x) for x in d.values())

Or if you don't mind importing a library:

import itertools as it
sum(it.chain(*d.values()))

Answer 5

Good solutions already here, but this is another way

sum(sum(a) for a in d.values())

Answer 6

One version with itertools.chain:

from itertools import chain

d= {'a': [6,7,8], 'b':[30,-3, 5000], 'c':[200.6], 'd':[2,2,2,2,2,2,2]}

print(sum(chain(*d.values())))

Prints:

5262.6

Answer 7

One of the shortest way:-

sum( sum(d.values(), [] ) )

Output

5262.6