如何将带有字符串的文件中的数字转换为python列表中的整数

Question

I'm trying to read a file which contains both names and numbers but I don't know how to convert the numbers to integers because they are on the same line with a string. I also want to sort it with the numbers.

This is like a scoreboard system and I want to print the top 5 player's scores and their names. Their scores are appended to a text file after they play a game which is read. The text file will have many more player's scores and names.

the file looks like this (we will call it data.txt):

Jack, 14
Amy, 2
Rock, 58
Jammy, 44

Once read, this is what the list looks like:

['Jack, 14', 'Amy, 2', 'Rock, 58', 'Jammy, 44']

This is what I have done so far:

file = open("data.txt", "r")
Data = file.readlines()
Data = [line.rstrip('\n') for line in Data]

I have tried these:

Data.sort(key = lambda x: x[1])

Data = list(map(int, Data))

However, it shows an error because there is also a string on the same line which I don't want to be converted to an integer.

What I'm hoping to be output is:

Amy, 2
Jack, 14
Jammy, 44
Rock, 58

I just want to know how to sort by the numbers (scores) in ascending order with a newline.

Answer 1

You could use the following key when sorting:

data = ['Jack, 14', 'Amy, 2', 'Rock, 58', 'Jammy, 44']
data.sort(key=lambda s: int(s.split(',')[1].strip()))
print(data)

Output

['Amy, 2', 'Jack, 14', 'Jammy, 44', 'Rock, 58']

The idea is to split the string on ',' then remove any trailing whitespace from the second element and convert to an int.

Answer 2

It's probably best to store the names and scores in pairs rather than as a string

from operator import itemgetter as ig
sorted_pairs = sorted(((pair[0], int(pair[1])) for pair in (line.split(', ') for line in file.readlines())), key = ig(0))