"Chris Castillo" <ctc...@gmail.com> wrote
I am trying to open a text file and read multiple lines containing the
following:
745777686,Alam,Gaus,CIS,15,30,25,15,5,31,15,48,70,97
888209279,Anderson,Judy,Math Ed,14,30,30,13,11,30,16,18,58,72
You could use the CSV module for this, although a basic
for loop is fine too if the data is this simple.
I want to ask the user for the student number, check to see if that
number is even valid and display something like:
You might want to store the data in a dictionary keyed by ID number?
#Open and read text file
gradesfile = open("grades.dat", "r"
for lines in gradesfile:
lines = lines.split(",")
identifier = lines[0]
lastname = lines[1]
firstname = lines[2]
major = lines[3]
OK so far
hw1 = lines[4]
hw2 = lines[5]
hw3 = lines[6]
hw4 = lines[7]
hw5 = lines[8]
hw6 = lines[9]
hw7 = lines[10]
You could store these in a list using list slicing, and convert
to numbers using a list comprehension
hw = [float(n) for n in lines[4:11]]
test1 = lines[11]
test2 = lines[12]
test3 = lines[13]
And here:
test = [float(n) for n in lines[11:14]]
totalpoints = 550
hwgrades = float(hw1) + float(hw2) + float(hw3) + float(hw4) +
float(hw5) + float(hw6) + float(hw7)
You could then use sum() to get the totals
hwgrades = sum(hw)
testgrades = float(test1) + float(test2) + float(test3)
testgrades = sum(test)
studentpoints = float(hwgrades) + float(testgrades)
you don;t need the flooat conversions because you already
did that above.
avgrades = round(float(studentpoints / totalpoints) * 100.0, 2)
same here.
print identifier
gradesfile.close()
That's what I have so far but I have a feeling I shouldn't use a for
loop. I would really like any help trying to figure out this program.
Thanks in advance.
Thats all fine for reading one stiudent, but you overwrite the
data each time through the loop! This also looks like an obvious
use for a class so I'd create a Student class to hold all the data
(You could create methods to do the totals/averages too, plus
add a __str__ method to print the student data in the format
required- I'll leave that as an excercise for the reader!))
So I'd change the structure to be like this(pseudo code)
students = dict() # empty dict
for line in gradesfile:
line = line.split(',')
s = Student()
s.id = line[0]
s.lastname = line[1]
etc....
s.hwtotal = sum(hw)
etc....
students[s.id] = s
Now you can access/print any student record with
id = raw_input('type an id number')
s = students[id]
print s
Finally you could put the for loop inside the Student
class __init__ method so it boils down to:
for line in gradesfile:
s = Student(line)
students[s.id] = s
In fact you could cram it all into one line with another
list comprehension, but that seems like a step too far to me...
HTH,
--
Alan Gauld
Author of the Learn to Program web site
http://www.alan-g.me.uk/
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