This tutorial will show you how to convert an
- octal escape sequence to a Python string, and a
- Python string to an octal escape sequence.
But let’s quickly recap what an octal escape sequence is in the first place! π

What Is An Octal Escape Sequence?π‘
An Octal Escape Sequence is a backslash followed by 1-3 octal digits (0-7
) such as \150
which encodes the ASCII character 'h'
. Each octal escape sequence encodes one character (except invalid octal sequence \000
). You can chain together multiple octal escape sequences to obtain a word.
Problem Formulation
π¬ Question: How to convert an octal escape sequence to a string and vice versa in Python?
Examples
Octal | String |
---|---|
\101 | 'ABC' |
| 'A B C' |
\141 | 'abc' |
\150 | 'hello' |
\150 | 'hello world' |
Python Octal to String Built-In Conversion
You don’t need to “convert” an octal escape sequence to a Unicode string if you already have it represented by a bytes object. Python automatically resolves the encoding.
See here:
>>> b'\101\102\103' b'ABC' >>> b'101\040\102\040\103' b'101 B C' >>> b'\101\040\102\040\103' b'A B C' >>> b'\141\142\143' b'abc' >>> b'\150\145\154\154\157' b'hello' >>> b'\150\145\154\154\157\040\167\157\162\154\144' b'hello world'
Python Octal to String Explicit Conversion
The bytes.decode('unicode-escape')
function converts a given bytes
object represented by an (octal) escape sequence to a Python string. For example, br'\101'.decode('unicode-escape')
yields the Unicode (string) character 'A'
.
def octal_to_string(x): ''' Converts an octal escape sequence to a string''' return x.decode('unicode-escape')
Example: Convert the octal representations presented above:
octals = [br'\101\102\103', br'\101\040\102\040\103', br'\141\142\143', br'\150\145\154\154\157', br'\150\145\154\154\157\040\167\157\162\154\144'] for octal in octals: print(octal_to_string(octal))
This leads to the following expected output:
ABC
A B C
abc
hello
hello world
Python String to Octal
To convert a Python string to an octal escape sequence representation, iterate over each character c
and convert it to an octal escape sequence using oct(ord(c))
.
The result uses octal representation such as '0o123'
. You can do string manipulation, such as slicing and string concatenation, to bring it into the final version '\123'
, for instance.
Here’s the function that converts string to octal escape sequence format:
def string_to_octal(x): ''' Converts a string to an octal escape sequence''' return '\\' + '\\'.join(oct(ord(c))[2:] for c in x)
β Background:
- The
ord()
function takes a character (=string of length one) as an input and returns the Unicode number of this character. For example,ord('a')
returns the Unicode number97
. The inverse function oford()
is thechr()
function, sochr(ord('a'))
returns the original character'a'
. - The
oct()
function takes one integer argument and returns an octal string with prefix"0o"
.
Let’s check how our strings can be converted to the octal escape sequence representation using this function:
strings = ['ABC', 'A B C', 'abc', 'hello', 'hello world'] for s in strings: print(string_to_octal(s))
And here’s the expected output:
\101\102\103
\101\40\102\40\103
\141\142\143
\150\145\154\154\157
\150\145\154\154\157\40\167\157\162\154\144
If you don’t like the one-liner solution provided above, feel free to use this multi-liner instead that may be easier to read:
def string_to_octal(x): ''' Converts a string to an octal escape sequence''' result = '' for c in x: result += '\\' + oct(ord(c))[2:] return result
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