This program sorts student grade information
Enter the name of the data file: p2sortin.py
Traceback (most recent call last):
  File "C:\Python23\p2sort.py", line 37, in ?
    main()
  File "C:\Python23\p2sort.py", line 31, in main
    data = readStudents(filename)
  File "C:\Python23\p2sort.py", line 11, in readStudents
    for line in infile:
ValueError: I/O operation on closed file
>>>

from gpa import Student, makeStudent
def readStudents(filename):
    infile = open(filename, 'r')
    students = []
    for line in infile:
        students.append(makeStudent(line))
        infile.close()
    return students
 
def writeStudents(students, filename):
    outfile = open(filename, 'w')
    for s in students:
        outfile.write("%s\t%f\t%f\n" %
                      (s.getName(), s.getHours(), s.getQPoints()))
        outfile.close()
 
def cmpGPA(s1, s2):
    return cmp(s1.gpa(), s2.gpa())
def main():
    print "This program sorts student grade information"
    filename = raw_input("Enter the name of the data file: ")
    data = readStudents(filename)
    data.sort(cmpGPA)
    filename = raw_input("Enter a name for the output file: ")
    writeStudents(data, filename)
    print "The data has been written to", filename
if __name__ == '__main__':
    main()

import string
import math
class Student:
    def __init__(self, name, hours, qpoints):
        self.name = name
        self.hours = float(hours)
        self.qpoints = float(qpoints)
    def getName(self):
        return self.name
    def getHours(self):
        return self.hours
    def getQPoints(self):
        return self.qpoints
    def gpa(self):
        return self.qpoints/self.hours
def makeStudent(infoStr):
    name, hours, qpoints = string.split(infoStr,"\t")
    return Student(name, hours, qpoints)
def main():
    filename = raw_input("Enter name the grade file: ")
    infile = open(filename, 'r')
    best = makeStudent(infile.readline())
    for line in infile:
        s = makeStudent(line)
        if s.gpa() > best.gpa():
            best = s
    infile.close()
    print "The best student is:", best.getName()
    print "hours:", best.getHours()
    print "GPA:", best.gpa()
if __name__ == '__main__':
    main()

Adams, Henry 127 228
Computewell, Susan 100 400
DibbleBit, Denny 18 41.5
Jones, Jim 48.5 155
Smith, Frank 37 125.33