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I have Directory structure like this

projectfolder/fold1/fold2/fold3/script.py

now I'm giving script.py a path as commandline argument of a file which is there in 

fold1/fold_temp/myfile.txt

So basically I want to be able to give path in this way 

../../fold_temp/myfile.txt 

>>python somepath/pythonfile.py -input ../../fold_temp/myfile.txt

Here problem is that I might be given full path or relative path so I should be able to decide and based on that I should be able to create absolute path.

I already have knowledge of functions related to path.

Question 1

Question 2

Reference questions are giving partial answer but I don't know how to build full path using the functions provided in them.

Community
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niyant
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  • If the user passed in a correct path, why do you care whether it is absolute or relative? Python certainly doesn't care, and your user probably doesn't care. – tripleee Sep 29 '15 at 08:52
  • Possible duplicate of [How to get an absolute file path in Python](https://stackoverflow.com/questions/51520/how-to-get-an-absolute-file-path-in-python) – Tobias Kienzler Jul 14 '17 at 13:20

4 Answers4

90

try os.path.abspath, it should do what you want ;)

Basically it converts any given path to an absolute path you can work with, so you do not need to distinguish between relative and absolute paths, just normalize any of them with this function.

Example:

from os.path import abspath
filename = abspath('../../fold_temp/myfile.txt')
print(filename)

It will output the absolute path to your file.

EDIT:

If you are using Python 3.4 or newer you may also use the resolve() method of pathlib.Path. Be aware that this will return a Path object and not a string. If you need a string you can still use str() to convert it to a string.

Example:

from pathlib import Path
filename = Path('../../fold_temp/myfile.txt').resolve()
print(filename)
Salo
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    provide a small example ... it is better than a link; otherwise, a good answer and would be up-voted... – IAbstract Feb 04 '18 at 14:34
5

A practical example:

sys.argv[0] gives you the name of the current script

os.path.dirname() gives you the relative directory name

thus, the next line, gives you the absolute working directory of the current executing file.

cwd = os.path.abspath(os.path.dirname(sys.argv[0]))

Personally, I always use this instead of os.getcwd() since it gives me the script absolute path, independently of the directory from where the script was called.

Lucas Azevedo
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4

For Python3, you can use pathlib's resolve functionality to resolve symlinks and .. components.

You need to have a Path object however it is very simple to do convert between str and Path.

I recommend for anyone using Python3 to drop os.path and its messy long function names and stick to pathlib Path objects.

Bryce Guinta
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-1
import os
dir = os.path.dirname(__file__)
path = raw_input()
if os.path.isabs(path):
    print "input path is absolute"
else:
    path = os.path.join(dir, path)
    print "absolute path is %s" % path

Use os.path.isabs to judge if input path is absolute or relative, if it is relative, then use os.path.join to convert it to absolute

Hooting
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    This doesn't work as a solution as in dir path you will have a path for script file where as according to question I don't want to give that as a path.. – niyant Sep 29 '15 at 08:51
  • Similer solution is there in links provided in question... it is perfectly fine if your input file is in same directory or in some subdirectory having same parent – niyant Sep 29 '15 at 08:53
  • `os.path.join(dir, path)` is already equal to `path`, if `path` is absolute (tested on Pyhon 3.6). – Mitar Oct 06 '17 at 23:18
  • I am facing another situation, this method works for me, thank you – Lancer.Yan Aug 16 '21 at 14:44