Python DefaultDict Ordering Multiple Values Issue

Question

I am trying to order all of the scores in order of each user's score from highest to lowest. I have attempted this with the code below:

import collections 
from collections import defaultdict
from operator import itemgetter

worker_scores = collections.defaultdict(lambda: collections.deque(maxlen=3))
import operator

worker_scores.clear() 

with open('score_names.txt') as f:
     for line in f: 
        worker,score = line.split(":")
        worker_scores[worker].append(int(score)) 

print("\nThis prints all the highest scores.\n")

for worker in sorted(worker_scores, key=itemgetter(1,2,3), reverse=True):
   print(worker," ".join(map(str,worker_scores[worker])))

   # This should print the maximum value for each key
   print max(worker_scores, key=worker_scores.get)

My text file also appears as follows:

AdamJohnson:10
AdamJohnson:20
AdamJohnson:30
AdamJohnson:40
AdamJohnson:60
AdamJohnson:50 
MichaelJordan:70
MichaelJordan:80
MichaelJordan:100
MichaelJordan:90
DavidSnowman:15
DavidSnowman:20
DavidSnowman:30
DavidSnowman:25

The outcome of the IDLE is as follows:

This prints all the highest scores.

MichaelJordan 80 100 90
AdamJohnson 40 60 50
DavidSnowman 20 30 25

This is what I desired, where the highest scores are at the top and the lowest scores are at the bottom. I discovered the itemgetter technique to do this so I have now accomplished part of my solution.

For the second part, I want the maximum key for each value to be printed. I can use the sorted key to print the keys in alphabetical order, but I cannot print the maximum value for each key. I have used this line from above:

print max(worker_scores, key=worker_scores.get)

To get this result:

AdamJohnson:60
MichaelJordan:100
DavidSnowman:30

But this error arrives: Invalid Syntax (Max). What is going wrong?

Answer 1

Also, if I want to print out my dictionary in order of highest results to lowest results, I would need to use itemgetter(1) since I am looking at the second value, which has the highest score and then using the reverse property set to True in order to indicate that the dictionary must be printed with highest at the top and lowest to the bottom.

Please see Sort a Python dictionary by value if you do not understand. I have just found this answer.

Thanks again to @KasraAD and @AnttiHaapala, alongside @PM2ring for their support, and my apologies to @jonrsharpe. I have now successfully answered my own question!

This is the code:

for k,v in sorted(d.items(), key=itemgetter(1), reverse=True):
    print (':'.join((k,str(v))))

Answer 2

You don't need to use max, you can use sorted function and collections.OrderedDict :

d=OrderedDict()

for k,v in sorted(((i,j.pop()) for i,j in worker_scores.items()),key=operator.itemgetter(1),reverse=True):
    d[k]=v

print d
OrderedDict([('MichaelJordan', 100), ('DavidSnowman', 30), ('AdamJohnson', 60)])

All that i have done in preceding code is loop over the worker_scores items and pop the last (max) element in deque,(j.pop()) but note that you need to use reverse=True to have the desire order, then add them to OrderedDict.

And for print the items :

for k,v in d.items():
    print ':'.join((k,str(v)))

MichaelJordan:100
DavidSnowman:30
AdamJohnson:60