Question

I am fairly new to programing and this is my first stab at creating a complex script using Python

The purpose of the program I am creating is:

• to go through a list of files (360 files altogether in a single folder)
• extract 3 unique characters in the file name and create a folder based on the 3 characters (60 unique folders altogether)
• create a for loop which goes through the list of files in the source folder and moves it to its corresponding target folder.

Example:

file name: KPHI_SDUS81_N3KDIX_201205261956

folder created based on characters: N3K

import os

#Creates a list based on file names in the folder
srcfile=os.listdir("E:\\Learning Python\\Testing out\\thunderstorm stuff")

#Directiory of where the source files are located
srcpath= "E:\\Learning Python\\Testing out\\thunderstorm stuff"

#Creates a list based on the location of where folders will be lcoated.
#List will be empty since for loop has not ran yet
targetsrc=os.listdir("E:\\Learning Python\\Testing out\\test folder")

#path of where the new folders created will be located
targetpath = "E:\\Learning Python\\Testing out\\test folder"

#empty list created to hold a string of 3 characters (see for loop below)
list=[]

#A list to hold the unique string values. (see 2nd for loop below)
Target=[]

#the for loop below looks at a file and gooes to the character place holder index of   12 and looks at the characters UP TO 15.
#It then assigns the three characters to a variable x which then passes the the string (the 3 characters) to an empty list called list. 
for num in srcfile:
  x=num[12:15]
  list.append(x)

#a test to see if the for loop above was able to exact the three characters from the list
print list
print srcfile

#created to see how big the list is which should match the amount of files in folder
print len(srcfile)
print len (list)

#a function created to make a folder based on a list
def create(s):
  targetpath = "E:\\Learning Python\\Testing out\\test folder"
  test=os.mkdir(os.path.join(targetpath,s))

#a dummy variable holder for the for loop below
valhold = "null"

#a nested if statement inside a for loop.
#The for loop goes through all the string values in a list called "list" (assigned to folder in for loop) 
#and checks it against a list called valhold.  If folder and valhold are not equal,
#the values in folder are appened to a list called Target.append which holds unique values.
#The next step is to create a folder a folder based off the list value "valhold"
for folder in list:
  if folder != valhold:
      Target.append(folder)
      valhold=folder
      create(valhold)
  else:
      valhold=folder

#a nested for loop which goes through all the files in the folder for the list "sourcefile"
#and finds a matching filename
for dst in Target:
  wheretonumber=0
  whereto = targetsrc(wheretonumber)  #Name of folder for a given index value "targetsrc"
  for file in list:
      filenumber=0
      filename=srcfile(filenumber) #Name of file for a given index value "sourcefile"
      if file == dst:
          ##os.rename(filename(filenumber),whereto(wheretonumber))
          ##shutil.move(filename,whereto)
      filenumber= filenumber+1
wheretonumber=wheretonumber+1

I am able to do the first 2 things in my bullet point list above but having a hard time getting the 3rd one to work. I’ve looked into shutil.move, os.path.walk, and os.rename functions and have had no luck getting them to work. I keep getting the error:

whereto = targetsrc(wheretonumber)
TypeError: ‘list’ object is not callable

I have the os.rename and shutil.move commented out since I am trying different functions. Is my logic correct in the approach or am I missing something? Any suggestions on other functions to try or changes to my code to get it to move the files into a folder?

Answer 1

To remove duplicates from the list variable just use set() built-in. And don’t use list as a variable name, this shadows built-in list().

Lists are indexed with brackets [] not parens.

I can’t see where you’re assigning anything but empty list (you wrote it yourself: #List will be empty since for loop has not ran yet) to targetsrc. Empty list has no elements, so even L[0] will be out of range.

Try something like this:

import os
import shutil

srcpath = "E:\\Learning Python\\Testing out\\thunderstorm stuff"
srcfiles = os.listdir(srcpath)

destpath = "E:\\Learning Python\\Testing out\\test folder"

# extract the three letters from filenames and filter out duplicates
destdirs = list(set([filename[12:15] for filename in srcfiles]))


def create(dirname, destpath):
    full_path = os.path.join(destpath, dirname)
    os.mkdir(full_path)
    return full_path

def move(filename, dirpath):
    shutil.move(os.path.join(srcpath, filename)
                ,dirpath)

# create destination directories and store their names along with full paths
targets = [
    (folder, create(folder, destpath)) for folder in destdirs
]

for dirname, full_path in targets:
    for filename in srcfile:
        if dirname == filename[12:15]:
            move(filename, full_path)