How to loop in multiple file in python and process it one by one

Question

I want to write a program that read multiple files and processes them in one loop.

I want to search for the id in all files and take the mark of a student.

My code is:

iD = int(input("Enter the your ID: "))
mathFile = open ('COMP2101.txt','r')
itFile = open ('STAT1001.txt','r')
bioFile = open ('BIOL2101.txt','r')

for line in mathFile and itFile and bioFile:
    line = line.rstrip()
    part = line.split(" ")
    studentId = int(part[0])

    if studentId == iD:
        mathMark = part[1]
        print("math",mathMark)

    if studentId == iD:
        itMark = part[1]
        print("it",itMark)

    if studentId == iD:
        bioMark = part[1]
        print("lbio",bioMark)


mathFile.close()
itFile.close()
bioFile.close()

How can I map the file name to if statement?

You can merge all files to one map and then search it in map — Ivan Sheihets
– Ivan Sheihets, Commented Nov 20, 2017 at 12:08
can you please explain more. Because I try to use map function but does not work with me :( — user8233859
– user8233859, Commented Nov 20, 2017 at 12:11
Do you really need to do this with a single loop / for statement? If so, why? — Tom Dalton
– Tom Dalton, Commented Nov 20, 2017 at 12:14

timgeb · Accepted Answer · 2017-11-20 12:24:37Z

3

from itertools import izip_longest # zip_longest in Python 3

with open('COMP2101.txt') as f1, open('STAT1001.txt') as f2, open('BIOL2101.txt') as f3:
    for line_f1, line_f2, line_f3 in izip_longest(f1, f2, f3, fillvalue=<anything you want>):
        # code

can you please tell me what is wrong in my code and how i can improve it?

Consider this demonstration in order to understand what's happening with your

for line in mathFile and itFile and bioFile:

loop:

>>> for x in [1,2] and [3,4] and [5,6]: print(x)
... 
5
6

because

>>> [1,2] and [3,4] and [5,6]
[5, 6]

How to improve it? Use my splendid answer, of course! :)

edited Nov 20, 2017 at 12:24

answered Nov 20, 2017 at 12:11

timgeb

79.2k20 gold badges129 silver badges150 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

user8233859 Over a year ago

can you please tel me what wrong in my cod and how i can to improve it ?

user8233859 Over a year ago

What about if i change and with coma , does it work ?

timgeb Over a year ago

@prog no, it will not. What's wrong with the solution I gave you?

timgeb Over a year ago

@prog good, trying to understand what went wrong is the right approach. If you are unsure whether something works, you don't need to ask me however. Just try it!

user8233859 Over a year ago

Thank you. I will try :)

Tom Dalton · Accepted Answer · 2017-11-20 12:12:14Z

1

Something like

filenames = {
    'Math': 'COMP2101.txt',
    'IT': 'STAT1001.txt',
    'Biology': 'BIOL2101.txt',
}
for subject, filename in filenames.items():
    with open(filename, 'r') as f:
        for line in f:
            line = line.rstrip()
            ...
            if studentId == iD:
                mark = part[1]
                print(subject, mark)

answered Nov 20, 2017 at 12:12

Tom Dalton

6,19027 silver badges36 bronze badges

2 Comments

Arun Over a year ago

He wants to do it in single loop.

user8233859 Over a year ago

can you please tel me what wrong in my cod and how i can to improve it ?

Collectives™ on Stack Overflow

How to loop in multiple file in python and process it one by one

2 Answers 2

5 Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

5 Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related