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Python replace Double Backlash with Single Bcklash

I am trying to convert the window path in Pathlib to string.
However, I can't convert the \\ to \
The code I ran
fileDir = pathlib.Path(self.CURRENTDATAPATH)
fileExt = r"*.xlsx"
for item in list(pathlib.Path(fileDir).glob(fileExt)):
self.XLSXLIST.append( str(item).replace( '\\\\', "\\") )
Got the result:
['D:\\data\\test.xlsx']
I would like to get this result
['D:\data\test.xlsx']

Backslash is used to escape special character in string. To escape a backslash you should use another backslash infront of it '\\'
When contructing string, you can use a leading r symbol before the raw string to avoid escaping.
print(r'\a\b\c')
the output is
\a\b\c
The echo output will always display in the escaped style, but this will not effect your use.
# echo of string s=r'\a\b\c'
'\\a\\b\\c'
So, your code is running as you wish, and the output is correct, just with another displaying format.

Rewritting a path - duplicate the backslash "\"

Let's say that I have this path :
path = "\\main\user\program\mathlab\test\count"
I want to rewrite this path to be able to use it. So I need to duplicate the backslash to get :
new_path = "\\\main\\user\\program\\mathlab\\test\\count"

This should do the job:
path.replace("\\", "\\\\") # replaces each \ with \\
We need two backslashes to represent one actual backslash. This is because a single backslash starts an escape sequence (of 2 characters total) that gives you the ability to represent characters like whitespaces (e.g. \n for newline, \t for tabs, ...). If you need it to give you a slash, you will have to add another slash to finish the sequence.

I have a file location stored in a reach file. Like \reach. It thinks it is a carriage return

My file location is detecting the \r in \reach as a carriage return.
There is nothing I could find online about the topic. I need it to list the file location as only a string.

Declare your string as a raw string by prefixing a r. A raw string ignores all backslashes.
location = r'\reach'
Alternatively you could use double backslashes like so
location = '\\reach'
A third way would be to just use forward slashes instead
location = '/reach'

You need to escape slash with another slash in the string: \\reach

It looks like you might be using windows as your os which uses '\' as separators.
You could try defining your file path in raw string. Eg.
f = open(r'dir1\dir2\reach')

Trouble loading csv file into Jupyter Notebooks [duplicate]

This question already has answers here:
How should I write a Windows path in a Python string literal?
(5 answers)
Closed 3 years ago.
I'm trying to read a CSV file into Python (Spyder), but I keep getting an error. My code:
import csv
data = open("C:\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener")
data = csv.reader(data)
print(data)
I get the following error:
SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes
in position 2-3: truncated \UXXXXXXXX escape
I have tried to replace the \ with \\ or with / and I've tried to put an r before "C.., but all these things didn't work.

This error occurs, because you are using a normal string as a path. You can use one of the three following solutions to fix your problem:
1: Just put r before your normal string. It converts a normal string to a raw string:
pandas.read_csv(r"C:\Users\DeePak\Desktop\myac.csv")
2:
pandas.read_csv("C:/Users/DeePak/Desktop/myac.csv")
3:
pandas.read_csv("C:\\Users\\DeePak\\Desktop\\myac.csv")

The first backslash in your string is being interpreted as a special character. In fact, because it's followed by a "U", it's being interpreted as the start of a Unicode code point.
To fix this, you need to escape the backslashes in the string. The direct way to do this is by doubling the backslashes:
data = open("C:\\Users\\miche\\Documents\\school\\jaar2\\MIK\\2.6\\vektis_agb_zorgverlener")
If you don't want to escape backslashes in a string, and you don't have any need for escape codes or quotation marks in the string, you can instead use a "raw" string, using "r" just before it, like so:
data = open(r"C:\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener")

You can just put r in front of the string with your actual path, which denotes a raw string. For example:
data = open(r"C:\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener")

Consider it as a raw string. Just as a simple answer, add r before your Windows path.
import csv
data = open(r"C:\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener")
data = csv.reader(data)
print(data)

Try writing the file path as "C:\\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener" i.e with double backslash after the drive as opposed to "C:\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener"

Add r before your string. It converts a normal string to a raw string.

As per String literals:
String literals can be enclosed within single quotes (i.e. '...') or double quotes (i.e. "..."). They can also be enclosed in matching groups of three single or double quotes (these are generally referred to as triple-quoted strings).
The backslash character (i.e. \) is used to escape characters which otherwise will have a special meaning, such as newline, backslash itself, or the quote character. String literals may optionally be prefixed with a letter r or R. Such strings are called raw strings and use different rules for backslash escape sequences.
In triple-quoted strings, unescaped newlines and quotes are allowed, except that the three unescaped quotes in a row terminate the string.
Unless an r or R prefix is present, escape sequences in strings are interpreted according to rules similar to those used by Standard C.
So ideally you need to replace the line:
data = open("C:\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener")
To any one of the following characters:
Using raw prefix and single quotes (i.e. '...'):
data = open(r'C:\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener')
Using double quotes (i.e. "...") and escaping backslash character (i.e. \):
data = open("C:\\Users\\miche\\Documents\\school\\jaar2\\MIK\\2.6\\vektis_agb_zorgverlener")
Using double quotes (i.e. "...") and forwardslash character (i.e. /):
data = open("C:/Users/miche/Documents/school/jaar2/MIK/2.6/vektis_agb_zorgverlener")

Just putting an r in front works well.
eg:
white = pd.read_csv(r"C:\Users\hydro\a.csv")

It worked for me by neutralizing the '' by f = open('F:\\file.csv')

The double \ should work for Windows, but you still need to take care of the folders you mention in your path. All of them (except the filename) must exist. Otherwise you will get an error.

How can I put an actual backslash in a string literal (not use it for an escape sequence)?

I have this code:
import os
path = os.getcwd()
final = path +'\xulrunner.exe ' + path + '\application.ini'
print(final)
I want output like:
C:\Users\me\xulrunner.exe C:\Users\me\application.ini
But instead I get an error that looks like:
SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 0-1: truncated \xXX escape
I don't want the backslashes to be interpreted as escape sequences, but as literal backslashes. How can I do it?
Note that if the string should only contain a backslash - more generally, should have an odd number of backslashes at the end - then raw strings cannot be used. Please use How can I get a string with a single backslash in it? to close questions that are asking for a string with just a backslash in it. Use How to write string literals in python without having to escape them? when the question is specifically about wanting to avoid the need for escape sequences.

To answer your question directly, put r in front of the string.
final= path + r'\xulrunner.exe ' + path + r'\application.ini'
But a better solution would be os.path.join:
final = os.path.join(path, 'xulrunner.exe') + ' ' + \
os.path.join(path, 'application.ini')
(the backslash there is escaping a newline, but you could put the whole thing on one line if you want)
I will mention that you can use forward slashes in file paths, and Python will automatically convert them to the correct separator (backslash on Windows) as necessary. So
final = path + '/xulrunner.exe ' + path + '/application.ini'
should work. But it's still preferable to use os.path.join because that makes it clear what you're trying to do.

You can escape the slash. Use \\ and you get just one slash.

You can escape the backslash with another backslash (\\), but it won’t look nicer. To solve that, put an r in front of the string to signal a raw string. A raw string will ignore all escape sequences, treating backslashes as literal text. It cannot contain the closing quote unless it is preceded by a backslash (which will be included in the string), and it cannot end with a single backslash (or odd number of backslashes).

Another simple (and arguably more readable) approach is using string raw format and replacements like so:
import os
path = os.getcwd()
final = r"{0}\xulrunner.exe {0}\application.ini".format(path)
print(final)
or using the os path method (and a microfunction for readability):
import os
def add_cwd(path):
return os.path.join( os.getcwd(), path )
xulrunner = add_cwd("xulrunner.exe")
inifile = add_cwd("application.ini")
# in production you would use xulrunner+" "+inifile
# but the purpose of this example is to show a version where you could use any character
# including backslash
final = r"{} {}".format( xulrunner, inifile )
print(final)