Develop Reference

Can't replace character "\"

I've been working on a program that reads out an specific PDF and converts the data to an Excel file. The program itself already works, but while trying to refine some aspects I ran into a problem. What happens is the modules I'm working with read directories with simple slashes dividing each folder, such as:
"C:/Users/UserX"
While windows directories are divided by backslashes, such as:
"C:\Users\UserX"
I thought using a simple replace would work just fine:
directory.replace("\" ,"/")
But whenever I try to run the program, the \ isn't identified as a string. Instead it pops up as orange in the IDE I'm working with (PyCharm). Is there anyway to remediate this? Or maybe another useful solution?

In general you should work with the os.path package here.
os.getcwd() gives you the current directory, you can add a subfolder of it via more arguments, and put the filename last.
import os
path_to_file = os.path.join(os.getcwd(), "childFolder", filename)

In Python, the '\' character is represented by '\\':
directory.replace("\\" ,"/")

Just try adding another backslash.
First of all you need to pass "C:\Users\UserX" as a raw string. Use
directory=r"C:\Users\UserX"
Secondly, suppress the backslash using a second backslash.
directory.replace("\\" ,"/")
All of this is required as in python the backslash (\) is a special character known as an escape character.

Try this:
import os
path = "C:\\temp\myFolder\example\\"
newPath = path.replace(os.sep, '/')
print(newPath)
Output:<< C:/temp/myFolder/example/ >>

Using os.system to operate a .py file on many files

I hope that I can ask this in a clear way, im very much a beginner to python and forums in general so I apologise if i've got anything wrong from the start!
My issue is that I am currently trying to use os.system() to enable a program to run on every file within a directory (this is a directory of ASCII tables which I am crossing with a series of other tables to find matches.
import os
for filename in os.listdir('.'):
os.system('stilts tmatch2 ifmt1=ascii ifmt2=ascii in1=intern in2= %s matcher=2d values1='col1 col2' values2='col1 col2' params=5 out= %s-table.fits'%(filename,filename))
So what im hoping this would do is for every 'filename' it would operate this program known as stilts. Im guessing this gets interrupted/doesn't work because of the presence of apostrophes ' in the line of code itself, which must disrupt the syntax? (please correct me if I am wrong)
I then replaced the ' in os.system() with "" instead. This, however, stops me using the %s notation to refer to filenames throughout the code (at least I am pretty sure anyway).
import os
for filename in os.listdir('.'):
os.system("stilts tmatch2 ifmt1=ascii ifmt2=ascii in1=intern in2= %s matcher=2d values1='col1 col2' values2='col1 col2' params=5 out= %s-table.fits"%(filename,filename))
This now runs but obviously doesn't work, as it inteferes with the %s input.
Any ideas how I can go about fixing this? are there any alternative ways to refer to all of the other files given by 'filename' without using %s?
Thanks in advance and again, sorry for my inexperience with both coding and using this forum!

I am not familiar with os.system() but maybe if you try do some changes about the string you are sending to that method before it could behave differently.
You must know that in python you can "sum" strings so you can save your commands in a variable and add the filenames as in:
os.system(commands+filename+othercommands+filename)
other problem that could be working is that when using:
for file in os.listdir()
you may be recievin file types instead of the strings of their names. Try using a method such as filename.name to check if this is a different type of thing.
Sorry I cant test my answers for you but the computer I am using is too slow for me to try downloading python.

saving/creating a file in a relative path with python 3

I'm new to Python and i'd like to build a script (Python 3) to test electronic modules and save log files.
I'd like to save the logfiles in the following format:
201410log.txt (yearmonthlog.txt)
This is done with the code:
import os
logfile=open(time.strftime('%Y%mlog.txt'), 'a')
logfile.write('This is a test\n\n\n')
This way, every month a new log file is created.
However, i'd like the logfiles to be in in a subdirectory (\logs).
I tried approaches like
logfile=open(time.strftime('\logs\%Y%mlog.txt'), 'a')
and similar things but i couldnt get any of them to work.
I searched trough other questions on stackoverflow (for example: Relative paths in Python ) and elsewhere in the internet, but i couldnt find the right solution.
Could someone point me in the right direction?
(sorry for any mistakes/spelling errors, i'm no native english speaker)

Remove the leading backslash. It makes the path absolute. Beside that, you need to escape a backslash.
logfile = open(time.strftime('logs\\%Y%mlog.txt'), 'a')
or use r'raw string literal':
logfile = open(time.strftime(r'logs\%Y%mlog.txt'), 'a')
For your current path string literal, it does not make problem. But paths like 'a\nb' will not work because \n is interpreted as newline instead of a literal backslash and n.

Open windows explorer at a specific network location in Python

I have tried so many variants of a theme to get this explorer window open at the P:\ drive, from what my little knowledge tells me, the fact the path to the folder is anywhere but the C:\ drive means it fails (it works with C:) so perhaps the path is wrong? the code below shows some of the tries i have made but still no luck, "P:" is mapped the same on all machines.
def Open_Win_Explorer_and_Select_Dir():
import subprocess
fldrname = os.path.basename(currentproject.get())
print(fldrname)
#subprocess.Popen('c:\windows\EXPLORER.EXE', cwd=(P:/Projects 2013/)
#subbprocess.Popen('c:\\windows\\EXPLORER.EXE' cwd=('P:\\Projects_2013\\')fldrname)
#subprocess.Popen(r'C:/Windows/explorer.exe', cwd=r'//WRDBSVR/Project_Data/Projects_2013/'+fldrname)
subprocess.Popen('explorer /n, /select r"\\192.168.0.27\\Project_Data\\Projects_2013\\"'+fldrname)
#subprocess.Popen('explorer /n, /select r"P:\\Project_Data\\Projects_2013\\"'+fldrname)

well to open My pc (for windows) try:
import subprocess
subprocess.Popen('explorer ""')
"#if subprocess.Popen('explorer "{0}".format(full_path)') is struck at pc\my documents.
where full_path=os.path.join("your/path")"

Appart from the fact that Ashish Nitin Patil's answer is definitly better, as using a variable for paths is always a good idea, you have a problem with your quotes:
# This line is not correct
'explorer /n, /select r"\\192.168.0.27\\Project_Data\\Projects_2013\\"'+fldrname
# ^you start a new string without ending previous one
# this one is correct
'explorer /n, /select ' + r'\192.168.0.27\Project_Data\Projects_2013\' + fldrname
# ^first ending string start
Besides, using raw strings (r"xxx") means that \ will not escape characters, so you shall not double them. If you want to double them, you do not need prepend r.
Last remark: take care to avoid string concatenation (+) when working with paths; you should use os.path.join() instead.

Following should do the job.
import subprocess
subprocess.Popen('explorer "{0}"'.format(full_folder_path))
Update -
Tested on my system -
full_path = os.path.join("P:/Project_Data/Projects_2013/",fldrname)
print full_path # Verify that it is correct
subprocess.Popen('explorer "{0}"'.format(full_path))

Python. Error when trying to create a new directory using the filename if it has a special character in it

My script searches the directory that it's in and will create new directories using the file names that it has found and moves them to that directory: John-doe-taxes.hrb -> John-doe/John-does-taxes.hrb. It works fine until it runs into an umlaut character then it will create the directory and return an "Error 2" saying that it cannot find the file. I'm fairly new to programming and the answers i've found have been to add a
coding: utf-8
line to the file which doesn't work I believe because i'm not using umlauts in my code i'm dealing with umlaut files. One thing I was curious about, does this problem just occur with umlauts or other special characters as well? This is the code i'm using, I appreciate any advice provided.
import os
import re
from os.path import dirname, abspath, join
dir = dirname(abspath(__file__))
(root, dirs, files) = os.walk(dir).next()
p = re.compile('(.*)-taxes-')
count = 0
for file in files:
match = p.search(file)
if match:
count = count + 1
print("Files processed: " + str(count))
dir_name = match.group(1)
full_dir = join(dir, dir_name)
if not os.access(full_dir, os.F_OK):
os.mkdir(full_dir)
os.rename(join(dir, file), join(full_dir, file))
raw_input()

I think your problem is passing strs to os.rename that aren't in the system encoding. As long as the filenames only use ascii characters this will work, however outside that range you're likely to run into problems.
The best solution is probably to work in unicode. The filesystem functions should return unicode strings if you give them unicode arguments. open should work fine on windows with unicode filenames.
If you do:
dir = dirname(abspath(unicode(__file__)))
Then you should be working with unicode strings the whole way.

One thing to consider would be to use Python 3. It has native support for unicode as the default. I'm not sure if you would have to do anything to change anything in the above code for it to work, but there is a python script in the examples to transition Python2 code to Python3.
Sorry I can't help you with Python2, I had a similar problem and just transitioned my project to Python3--ended up just being a bit easier for me!