如何在不使用 numpy 或在 Python 中展平的情况下在二维数组中找到最小值？

Question

Let's say that:

atable = [[6, 2, 3, 1], [3, 4, 2, 1], [4, 8, 7, 6], [8, 9, 3, 7]]

without using numpy or flattened, how would you find the minimum value of the entire list?

I assume you can use a list but I am not sure.

Answer 1

Here are several approaches:

from itertools import chain

atable = [[6, 2, 3, 1], [3, 4, 2, 1], [4, 8, 7, 6], [8, 9, 3, 7]]

# Flatten the sublists into a single list
result = min(chain.from_iterable(atable))

# Find the min of each list, the find the min of mins
result = min(map(min, atable))

# Use a generator expression with nested loops
result = min(i for lst in atable for i in lst)

Answer 2

Here is a brute force approach:

atable = [[6, 2, 3, 1], [3, 4, 2, 1], [4, 8, 7, 6], [8, 9, 3, 7]]
min_list = []
for l in atable:
    min_list.append(min(l))
min_val = min(min_list)

Answer 3

For your specific problem...

min(min(a_table))

As noted by @Prune this does not work. In fact min(a_table) returns the sublist with the smallest first element.