Posted by José Lopes

This post shows a range of solutions to find the maximum value of a set of lists, and the minimum value by analogy.

Supose, as an example, that you have the following lists:

A = [1, 2, 9]
B = [100, 50, 75]
C = [6, 2, 80]
D = [42, 33, 5]

We want to get 100 as the maximum and 1 as the minimum values.

Python's builtin functions that allow us to get these values are:

• max() - for the maximum value
• min() - for the minimum value

I'll show next some ways to ge the maximum value, being that for the minimum you just have to change max by min.
The solution you choose depends on the problem to solve and your personal programing style.

Solution 1

Lists = A,B,C,D
max([max(i) for i in Lists])

Solution 2

max([max(i) for i in (A, B, C, D)])

Solution 3

Lists = A,B,C,D
max(map(max,Lists))

Solution 4

Create a function:

def get_max(seq):
    try:
        return max(map(get_max, seq))
    except TypeError:
        return seq

To use it:

Lists = A,B,C,D
get_max(Lists)
# or:
get_max([A,B,C,D])

Solution 5

Lists = A,B,C,D
import itertools
max(itertools.chain(*Lists))