Python using open (w+) FileNotFoundError

Question

1. Creating function saveTxtIndividualTracks(track,folder,i).Based on python3.4.3 and windows 7:

   def saveTxtIndividualTracks(track,folder,i):
       f = open(folder+str(i)+'.txt','w+')
           for line in track:
               l=str(line[0])+','+str(line[1])+','+str(line[2])+'\n'
           f.write(l)
       f.close()
   

2. Using the function:

   saveTxtIndividualTracks(new,'E:/phoneTracks/'+track_name+'/',i)
   

When I ran the code, I got this error:

FileNotFoundError: [Errno 2] No such file or directory: 'E:/phoneTracks/TA92903URN7ff/0.txt'

I created folder phoneTracks in E. And I am confused open() function with mode 'w+', which is used to creat a new file. Why do I get a FileNotFoundError? What can I do to fix it?

Answer 1

You are getting the error because the directory - E:/phoneTracks/TA92903URN7ff/ does not exist.

Example to show this error -

In [57]: open('blah/abcd.txt','w+')
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
<ipython-input-57-46a07d4a5d18> in <module>()
----> 1 open('blah/abcd.txt','w+')

FileNotFoundError: [Errno 2] No such file or directory: 'blah/abcd.txt'

Got error in my code, because the directory blah/ does not exist.

If the directory - TA92903URN7ff/ is constant, try creating it and then running. If its not constant, you can checkout os.path.exists to check if the directory exists or not, and if it doesn't exist, create one using os.mkdir .

Example -

import os, os.path
def saveTxtIndividualTracks(track,folder,i):
    if not os.path.exists(folder):
         os.mkdir(folder)
    elif not os.path.isdir(folder):
         return #you may want to throw some error or so.
    f = open(os.path.join(folder, str(i)+'.txt'),'w+')
        for line in track:
            l=str(line[0])+','+str(line[1])+','+str(line[2])+'\n'
        f.write(l)
    f.close()

Also, you should consider using os.path.join to join paths, instead of using string concatenation. And also using with statement for openning files as - with open(os.path.join(folder, str(i)+'.txt'),'w+') as f: , that way the file will automatically get closed once the with block ends.