How To Sort File Contents Into List

I need a solution to sort my file like the following: Super:1,4,6 Superboy:2,4,9 My file at the moment looks like this: Super:1 Super:4 Super:6 I need help to keep track of the s

Solution 1:

You can use a dict to group the data, in particular a collections.OrderedDict to keep the order the names are seen in the original file:

from collections import OrderedDict

withopen("class.txt") as f:
    od = OrderedDict()
    for line in f:
        # n = name, s = score
        n,s = line.rstrip().split(":")
        # if n in dict append score to list # or create key/value pairing and append
        od.setdefault(n, []).append(s)

It is just a matter of writing the dict keys and values to a file to get the output you want using the csv module to give you nice comma separated output.

from collections import OrderedDict
import csv
with open("class.txt") as f, open("whatever.txt","w") asout:
    od = OrderedDict()
    for line in f:
        n,s = line.rstrip().split(":")
        od.setdefault(n, []).append(s)
    wr = csv.writer(out)
    wr.writerows([k]+v for k,v in od.items())

If you want to update the original files, you can write to a tempfile.NamedTemporaryFile and replace the original with the updated using shutil.move:

from collections import OrderedDict
import csv
from tempfile import NamedTemporaryFile
from shutil import move

withopen("class.txt") as f, NamedTemporaryFile("w",dir=".",delete=False) as out:
    od = OrderedDict()
    for line in f:
        n, s = line.rstrip().split(":")
        od.setdefault(n, []).append(s)
    wr = csv.writer(out)
    wr.writerows([k]+v for k,v in od.items())
# replace original file
move(out.name,"class.txt")

If you have more than one class just use a loop:

classes = ["foocls","barcls","foobarcls"]

for cls in classes:
    withopen("{}.txt".format(cls)) as f, NamedTemporaryFile("w",dir=".",delete=False) as out:
        od = OrderedDict()
        for line in f:
            n, s = line.rstrip().split(":")
            od.setdefault(n, []).append(s)
        wr = csv.writer(out)
        wr.writerows([k]+v for k,v in od.items())
    move(out.name,"{}.txt".format(cls))

Solution 2:

I'll provide some pseudocode to help you out.

First your data structure should look like this:

data = {'name': [score1, score2, score3]}

Then the logic you should follow should be something like this:

Read the file line-by-line
    if name is already in dict:
       append score to list. example: data[name].append(score)
    if name isnotin dict:
       create new dict entry. example: data[name] = [score]

Iterate over dictionary and write each line to file