CODEWITHSUNDEEP
pythonfile
this.is.not.a.nick
this.is.not.a.nick

Reputation: 2701

Choose a file starting with a given string

In a directory I have a lot of files, named more or less like this:

001_MN_DX_1_M_32
001_MN_SX_1_M_33
012_BC_2_F_23
...
...

In Python, I have to write a code that selects from the directory a file starting with a certain string. For example, if the string is 001_MN_DX, Python selects the first file, and so on.

How can I do it?

Upvotes: 74

Views: 182920

Answers (8)

ccpizza
ccpizza

Reputation: 31726

With Python3 you can use pathlib.Path as follows:

Path(root_dir).glob('*001_MN_DX*')

And if you need recursive globbing in subdirs:

Path(root_dir).glob('**/*001_MN_DX*')

# OR (same effect as above)
Path(root_dir).rglob('*001_MN_DX*')

Docs:

Upvotes: 2

Marc Laugharn
Marc Laugharn

Reputation: 1357

import os
prefixed = [entry for entry in os.listdir('.') if entry.startswith("prefix") and os.path.isfile(entry)]

Upvotes: 100

gregV
gregV

Reputation: 1107

with newer pathlib module, see link:

from pathlib import Path
myDir = Path('my_directory/')

fileNames = [file.name for file in myDir.iterdir() if file.name.startswith('prefix')]    
filePaths = [file for file in myDir.iterdir() if file.name.startswith('prefix')]

Upvotes: 1

M Gui
M Gui

Reputation: 41

import os
 for filename in os.listdir('.'):
    if filename.startswith('criteria here'):
        print filename #print the name of the file to make sure it is what 
                               you really want. If it's not, review your criteria
                #Do stuff with that file

Upvotes: 3

ErenO
ErenO

Reputation: 261

You can use the module glob, it follows the Unix shell rules for pattern matching. See more.

from glob import glob

files = glob('*001_MN_DX*')

Upvotes: 24

pradyunsg
pradyunsg

Reputation: 19446

Try using os.listdir,os.path.join and os.path.isfile.
In long form (with for loops),

import os
path = 'C:/'
files = []
for i in os.listdir(path):
    if os.path.isfile(os.path.join(path,i)) and '001_MN_DX' in i:
        files.append(i)

Code, with list-comprehensions is

import os
path = 'C:/'
files = [i for i in os.listdir(path) if os.path.isfile(os.path.join(path,i)) and \
         '001_MN_DX' in i]

Check here for the long explanation...

Upvotes: 62

sansxpz
sansxpz

Reputation: 111

You can use the os module to list the files in a directory.

Eg: Find all files in the current directory where name starts with 001_MN_DX

import os
list_of_files = os.listdir(os.getcwd()) #list of files in the current directory
for each_file in list_of_files:
    if each_file.startswith('001_MN_DX'):  #since its all type str you can simply use startswith
        print each_file

Upvotes: 7

Xiaowei Song
Xiaowei Song

Reputation: 161

import os, re
for f in os.listdir('.'):
   if re.match('001_MN_DX', f):
       print f

Upvotes: 9

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