Trying to write to csv from input , csv output file shows each name with colons between letters and-CodePudding

import csv 
n = int(input("How many records ?"))
b = 0
for i in range(n):


   s = input("what is the name of the student  ")
   g = input(" grade ?")
   k.append(s),k.append(g)
 print("res",'[%s]'%', '.join(map(str, k)))

StuGrade = "StuGrade.csv"
with open(StuGrade, 'w' ) as f :
    thewriter = csv.writer(f)
    thewriter.writerow( k[0])
    for i in range(n*2-1) :
        b=b 1
        thewriter.writerow( k[b])

This is the output of my program:

How many records 1

what is the name of the student  ahmad 
 grade ? 3
res [ahmad ,  3]

The csv file looks like this:

a,h,m,a,d,

,3

I want it like that:

ahmad
3

CodePudding user response：

csv.writerow() takes a list of values for that row - you are supplying single values. Strings are iterables - if you give one string to csv.writerow() it will use every single letter as 1 column. You could fix that supplying it as 1 element list:

 thewriter.writerow( [ k[b] ] )  # 1 element list

To write a csv correctly (with single or with multiple values per row and multiple rows) you are missing a newline="" when opening the file (this is well documented) to create the csv file correctly - missing this introduces the empty line in your current output.

with open(StuGrade, 'w', newline = "") as f :  # add  newline = ""

You do not really need a csv writer to create a file with 1 thing per line:

with open("file.txt","w") as f:
    for word in k:               # dont use index iterating, use element itering
        f.write(word   "\n")

would do it.

Fix/Demo for 2 values per line:

import csv 

k = ["ABC","5", "BCD","7", "CDE","42"]

StuGrade = "StuGrade.csv"
with open(StuGrade, 'w', newline = "") as f :  # added newline
    thewriter = csv.writer(f)

    # go over the range of input indexes and increase by 2       
    for idx in range(0, len(k), 2):
        # slice and write 2 values as 2 columns from your k list at once 
        thewriter.writerow( k[idx : idx 2]) 

print(open("StuGrade.csv").read())

Output:

ABC,5
BCD,7
CDE,42