display an octal value as its string representation

问题

I've got a problem when converting an octal number to a string.

p = 01212
k = str(p)
print k

The result is 650 but I need 01212. How can I do this? Thanks in advance.

回答1:

Your number p is the actual value rather than the representation of that value. So it's actually 650₁₀, 1212₈ and 28a₁₆, all at the same time.

If you want to see it as octal, just use:

print oct(p)

as per the following transcript:

>>> p = 01212
>>> print p
650
>>> print oct(p)
01212

That's for Python 2 (which you appear to be using since you use the 0NNN variant of the octal literal rather than 0oNNN).

Python 3 has a slightly different representation:

>>> p = 0o1212
>>> print (p)
650
>>> print (oct(p))
0o1212

回答2:

One way is to usse the o format character from the Format Mini Specification Language:

Example:

>>> x = 01212
>>> print "0{0:o}".format(x)
01212

'o' Octal format. Outputs the number in base 8.

NB: You still have to prepend the 0 (Unless you use the builtin function oct()).

Update: In case you're using Python 3+:

$ python3.4
Python 3.4.0 (default, Apr 11 2014, 13:05:11) 
[GCC 4.8.2] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> x = 01212
  File "<stdin>", line 1
    x = 01212
            ^
SyntaxError: invalid token
>>> x = 0o1212
>>> print(oct(x))
0o1212
>>> print("0o{0:o}".format(x))
0o1212

来源：https://stackoverflow.com/questions/30160270/display-an-octal-value-as-its-string-representation

标签

python

format

octal