在python中搜索嵌套列表的最有效方法是什么？

Question

Let's say I've a nested loop where I've listed result of a particular subject of students with name like:

records = [[name, score]]

for example let's say we have list like these:

records = [['a', 67], ['b', 64], ['c', 63], ['d', 59]]

So here I want to print the maximum value with name? I'm still noob in python so it will be great if you explain in easy way. Thanks in advance <3

Answer 1

There are multiple ways of doing this. One of which is by using the inbuilt function max which finds the maximum value of its arguments. In this case an Array. Since we want to get the maximum value for the score, we need to get the integer from the array. We can do this by specifying a key function.

We can do this with an anonymous function lambda like this

records = [['a', 67], ['b', 64], ['c', 63], ['d', 59]]

print(max(records, key=lambda x: x[1]))

Or we can use a defined function like this

records = [['a', 67], ['b', 64], ['c', 63], ['d', 59]]
def getScore(x):
    return x[1]
print(max(records,key=getScore))

There is a simpler or more understandable way of doing this. Using the library operator and its function item getter

import operator

records = [['a', 67], ['b', 64], ['c', 63], ['d', 59]]
print(max(records,key=operator.itemgetter(1)))