Question

I have 125 data files containing two columns and 21 rows of data and I’d like to import them into a single .csv file (as 125 pairs of columns and only 21 rows).
This is what my data files look like:

I am fairly new to python but I have come up with the following code:

import glob
Results = glob.glob('./*.data')
fout='c:/Results/res.csv'
fout=open ("res.csv", 'w')
 for file in Results:
 g = open( file, "r" )
 fout.write(g.read())
 g.close() 
fout.close()

The problem with the above code is that all the data are copied into only two columns with 125*21 rows.

Any help is very much appreciated!

Answer 1

This should work:

import glob

files = [open(f) for f in glob.glob('./*.data')] #Make list of open files
fout = open("res.csv", 'w')

for row in range(21):
    for f in files:
        fout.write( f.readline().strip() ) # strip removes trailing newline
        fout.write(',')
    fout.write('\n')

fout.close()

Note that this method will probably fail if you try a large number of files, I believe the default limit in Python is 256.