Calculating average from Python Script

stryker213 · 04-25-2010, 02:15 PM

Hello, I'm trying to write a python script that will calculate my test scores from a text file named "exams."

Sample input would be:
Calculus 85 90
Physics 90 85 93

Output will look like:
Calculus 87.5
Physics 89.3

I have the following code:

Code:

#!/usr/bin/python
import math
import sys

f = open('exams',"r")
l = f.readline()
while l :
 l = l.split(None,10)
 L = l[1:]
 print sum
 print l[:1]
 print 'Scores ', L
 print 'Number of Values ', len(L)
 l = f.readline()

My intent is to sum the values found in L and divide by len(L).

I think my issue is that when I split the values, I get a string array (ex. ['85', '90'] ), which makes it hard to do calculations.

indienick · 04-25-2010, 02:29 PM

You can convert strings to integers in Python by passing the value to the int() function, like so:

Code:

>>> int('230498')
230498
>>>

Mara · 04-25-2010, 02:33 PM

print int(L[0])

The int operator gives you the conversion you need.

stryker213 · 04-25-2010, 02:35 PM

Quote:

Originally Posted by indienick

You can convert strings to integers in Python by passing the value to the int() function, like so:

Code:

>>> int('230498')
230498
>>>

Thanks for the advice indienick. However, it's still not working. My code takes each line of text and parses it into a array so that it looks like this: ['Calculus', '85', '90']. Using L = l[1:], gives me ['85', '90'], which is close. If I used your method (L = int(l[1:])), I get an error.

stryker213 · 04-25-2010, 02:38 PM

Quote:

Originally Posted by Mara

print int(L[0])

The int operator gives you the conversion you need.

Mara, thank you very much for your help. Your method does work for individual iterations, but how can I make it so that it goes through my entire exam list? For example, I may have two test scores for one subject and four in another.

Thanks again!

indienick · 04-25-2010, 04:58 PM

Maybe try something like this:

Code:

average = 0

for x in range(1, len(l)):
  score = int(l[x])
  average += score

average = float(average / (len(l) - 1))
print average