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Python - numbers change when included in a directory string

I've searched online and can't seem to find any other examples of this. Why is 2015 becoming x815 and how can I fix it?

>>> os.chdir("N:\PRTR\Weekly Estimate\2015")

Traceback (most recent call last):
  File "<pyshell#10>", line 1, in <module>
    os.chdir("N:\PRTR\Weekly Estimate\2015")
WindowsError: [Error 2] The system cannot find the file specified: 'N:\\PRTR\\Weekly Estimate\x815'
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2 answers


It \x

is actually an escape sequence, which means that the next two characters are interpreted as hexadecimal digits.

So, you will have:

>>> '\2015'
'\x815'


And in order to deal with this, you need to run \

:

>>> print '\\2015'
\2015
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Actually, in Python, "\" is an escape character in strings, and all special characters are created with "\" followed by one or more other specific characters. For example, "\n"

in a string, this is a new string character.

As it happens, "\" followed by three numbers denotes an eight-digit octal character. "\201"

matches the eighth character, which may appear as a hexadecimal number to a terminal that cannot print it x81

.

To avoid this, make your string a raw string by putting the letter r

in front, outside the quotes, for example



print r'N:\PRTR\Weekly Estimate\2105'

r

will force Python to interpret the string exactly as you typed it, ignoring all special characters and escape sequences, and you will get the desired result.

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