How to write to second column in csv python

I am writing the output of my code to the .csv file. There are three directories each directory contains 50-files. I want to write the output of each directory files in different column. LIKE;

       group1  group2 group3
file1 1445      89    87
file2 1225     100    47
file3 650      120    67
file4 230      140    97

I have following code to do so,

from collections import Counter
import glob
import os

out= open( 'output.csv','a')
out.write (';''group-1')
out.write (';''group-2')
out.write (';''group-3')
out.write('\n')
i = 1

while i<=50:
 out.write( "file-%d" %i )
 out.write('\n')
 i+=1
i=1
path = 'group/group-*-files/*.txt'

files=sorted(glob.glob(path))
c=Counter()

for filename in files:

 for line in open(filename,'r'):

    c.update(line.split())

 for item in c.items():
  oi=("{}\t{}".format(*item))  
  out_array = oi.split()

  if out_array[0]=='00000000':

   out.write(out_array[1])
   out.write('\n')
  c.clear()

The problem I am getting and did not able to solve, the answer starts writing in the first column after file number 50

file48
file49
file50
1445
1225
.. 

I want to write first 50 answers under group1 column, next 50 in group2 and last 50 in group3

final output looks like,

group1  group2 group3
file1 145      89     87
file2 850      100    47
file3 650      120    67
file4 230      140    97

asked Jun 29, 2017 at 13:49

9

This is how I would rewrite your code. The changes I made are:

• Use the with statement when opening files to make sure they get closed
• Use the csv module to make writing the csv file easier
• Write the whole line at once by building one line at a time before writing it to the file.

Since I don't really know what is in your files, this isn't thoroughly tested.

import csv
from collections import Counter
import glob
import os

with open( 'output.csv','a') as out:
    writer =csv.writer(out, delimiter='\t')
    writer.writerow(['']+['group{}'.format(i) for i in range(1, 4)])
    path = 'group/group-*-files/*.txt'

    files=sorted(glob.glob(path))
    c=Counter()
    for i, filename in enumerate(files):
        line = ['file-{}'.format(i)]
        with open(filename) as infile:
            for line in infile:
                c.update(line.split())
        for key, count in c.items():
            if key == '00000000':
                line.append(count)
        writer.writerow(line)
        c.clear()

answered Jun 29, 2017 at 14:21

You have at least one problem with the wrong indentation. You firstly generate all file names by this:

...
while i<=50:
 out.write( "file-%d" %i )
 out.write('\n')                # replace \n to column delimiter \t
 i+=1

And than you begin process the files. You delete this line i=1 and all other text must start at the same indentation as out.write

from collections import Counter
import glob
import os

out= open( 'output.csv','a')  # flag a - Do you want append to existing file ?
out.write('file;group-1;group2;group3') # You forget column 1 - filename
# out.write (';''group-1')
# out.write (';''group-2')
# out.write (';''group-3')
# out.write('\n')
i = 1
while i<=50:
 out.write( "file-%d" %i )
 # out.write('\n')
 out.write(';')    # Insert character for column delimiter
 i+=1
 # i=1  Delete, because will cause infinite loop
 # Following code must run inside while loop, indent to the same level
 # as previous lines
 path = 'group/group-*-files/*.txt'

 files=sorted(glob.glob(path))
 c=Counter()

 for filename in files:

  for line in open(filename,'r'):

     c.update(line.split())

  for item in c.items():
   oi=("{}\t{}".format(*item))  
   out_array = oi.split()

   if out_array[0]=='00000000':

    out.write(out_array[1])
    # out.write('\n') - You don want create new lines, but only new columns for every group
    out.write(';') 

   c.clear()
  out.write('\n') # New line - new record

marc_s

713k171 gold badges1314 silver badges1433 bronze badges

answered Jun 29, 2017 at 14:29

 for filename in files:
  for item in c.items():
   oi=("{}\t{}".format(*item))  
   out_array = oi.split()` for filename in files:

  for line in open(filename,'r'):

     c.update(line.split())

  for item in c.items():
   oi=("{}\t{}".format(*item))  
   out_array = oi.split()

toku-sa-n

6881 gold badge6 silver badges23 bronze badges

answered Jan 28 at 11:00

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