在 Python 中返回（副本）具有给定 id 的二维列表的一行的最有效（最快）方法是什么？

Question

What is the most efficient (quickest) way to return (a copy of) a row of a two-dimensional list with a given id in Python? The first element of each row is an ID (string). My function needs to search two-dimensional list for the row with the matching ID and return a copy of that row. If there is no match, it should return None.

Answer 1

If you're doing it only once, iterating over the list and checking the first element would be the best.

If you can pre-process the table, I suggest converting into a dictionary first:

d = {row[0]: row for row in lst}

and then searching:

d.get(id)

Slow list iteration (If you can't use a dict, as you specified in comments section):

for row in lst:
    if row[0] == id:
        break
else:
    row = None

Answer 2

If you really want to do this without changing the model you will need to do an O(n) search, but I highly question opting for this choice if you really want to optimize for speed as you mention in the description:

import copy


def find_element(data, id):
    for entry in data:
        if entry[0] == id:
            return copy.copy(entry)
    return None