How to find the average for a file then put it in another file

Question

I want to find the average of the list inFile and then I would like to move it to the classscores.

classgrades.txt is:

Chapman 90 100 85 66 80 55    
Cleese 80 90 85 88    
Gilliam 78 82 80 80 75 77    
Idle 91    
Jones 68 90 22 100 0 80 85    
Palin 80 90 80 90

classcores.txt is empty

This is what I have so far... what should I do?

inFile = open('classgrades.txt','r')
outFile = open('classscores.txt','w')

for line in inFile:
  with open(r'classgrades.txt') as data:
    total_stuff = #Don't know what to do past here

biggest = min(total_stuff)
smallest = max(total_stuff)
print(biggest - smallest)
print(sum(total_stuff)/len(total_stuff))

Answer 1

This script should accomplish what you are trying to do I think:

# define a list data structure to store the classgrades
classgrades = []

with open( 'classgrades.txt', 'r' ) as infile:
  for line in infile:
    l = line.split()
    # append a dict to the classgrades list with student as the key
    # and value is list of the students scores.
    classgrades.append({'name': l[0], 'scores': l[1:]})

with open( 'classscores.txt', 'w' ) as outfile:
  for student in classgrades:

    # get the students name out of dict.
    name = student['name']

    # get the students scores. use list comprehension to convert 
    # strings to ints so that scores is a list of ints.
    scores = [int(s) for s in student['scores']]

    # calc. total 
    total = sum(scores)

    # get the number of scores.
    count = len( student['scores'] )

    # calc. average
    average = total/count
    biggest = max(scores)
    smallest = min(scores)
    diff = ( biggest - smallest )

    outfile.write( "%s %s %s\n" % ( name, diff , average ))

Running the above code will create a file called classscores.txt which will contain this:

Chapman 45 79.33333333333333
Cleese 10 85.75
Gilliam 7 78.66666666666667
Idle 0 91.0
Jones 100 63.57142857142857
Palin 10 85.0

Answer 2

Apologies if this is kind of advanced, I try to provide key words/phrases for you to search for to learn more.

Presuming you're looking for each student's separate average:

in_file = open('classgrades.txt', 'r')  # python naming style is under_score
out_file = open('classcores.txt', 'w')
all_grades = []  # if you want a class-wide average as well as individual averages

for line in in_file:
    # make a list of the things between spaces, like ["studentname", "90", "100"]
    student = line.split(' ')[0]

    # this next line includes "list comprehension" and "list slicing"
    # it gets every item in the list aside from the 0th index (student name),
    # and "casts" them to integers so we can do math on them.
    grades = [int(g) for g in line.split(' ')[1:]]

    # hanging on to every grade for later
    all_grades += grades  # lists can be +='d like numbers can

    average = int(sum(grades) / len(grades))

    # str.format() here is one way to do "string interpolation"
    out_file.write('{} {}\n'.format(student, average))

total_avg = sum(all_grades) / len(all_grades)
print('Class average: {}'.format(total_avg))
in_file.close()
out_file.close()

As others pointed out, it is good to get in the habit of closing files. Other responses here use with open() (as a "context manager") which is best practice because it automatically closes the file for you. To work with two files without having a data container in between (like Amit's d1 dictionary), you would do something like:

with open('in.txt') as in_file:
    with open('out.txt', 'w') as out_file:
        ... do things ...

Answer 3

You will need to:
- split each line by whitespace and slice out all items but the first
- convert each string value in array to integer
- sum all of those integer values in the array
- add the sum for this line to total_sum
- add the length of those values (the number of numbers) to total_numbers

However, this is only part of the problem... I will leave the rest up to you. This code will not write to the new file, it will simply take an average of all the numbers in the first file. If this isn't exactly what you are asking for, then try playing around with this stuff and you should be able to figure it all out.

inFile = open('classgrades.txt','r')
outFile = open('classscores.txt','w')
total_sum = 0
total_values = 0
with open(r'classgrades.txt') as inFile:
  for line in  inFile:
    # split by whitespace and slice out everything after 1st item
    num_strings = line.split(' ')[1:] 

    # convert each string value to an integer
    values = [int(n) for n in num_strings]

    # sum all the values on this line
    line_sum = sum(values)

    # add the sum of numbers in this line to the total_sum
    total_sum += line_sum

    # add the length of values in this line to total_values
    total_numbers += len(values)

average = total_sum // total_numbers  # // is integer division in python3
return average

Answer 4

you don't need to open file many times and you should close the files at the end of your program. Below is what I tried hope this works for you:

d1 = {}
with open(r'classgrades.txt','r') as fp:
    for line in fp:
        contents = line.strip().split(' ')
        # create mapping of student and his numbers
        d1[contents[0]] = map(int,contents[1:])

with open(r'classscores.txt','w') as fp:
    for key, item in d1.items():
        biggest = min(item)
        smallest = max(item)
        print(biggest - smallest)
        # average of all numbers
        avg = sum(item)/len(item)
        fp.write("%s %s\n"%(key,avg))