Luc schrieb:
On Oct 8, 11:13 pm, "Diez B. Roggisch" <de...@nospam.web.de> wrote:
Luc schrieb:

Hi all,
I read data from a binary stream, so I get hex values as characters
(in a string) with escaped x, like "\x05\x88", instead of 0x05.
I am looking for a clean way to add these two values and turn them
into an integer, knowing that calling int() with base 16 throws an
invalid literal exception.
Any help appreciated, thanks.
Consider this (in the python interpreter):

 >>> chr(255)
'\xff'
 >>> chr(255) == r"\xff"
False
 >>> int(r"ff", 16)
255

In other words: no, you *don't* get hex values. You get bytes from the
stream "as is", with python resorting to printing these out (in the
interpreter!!!) as "\xXX". Python does that so that binary data will
always have a "pretty" output when being inspected on the REPL.

But they are bytes, and to convert them to an integer, you call "ord" on
them.

So assuming your string is read bytewise into two variables a & b, this
is your desired code:

 >>> a = "\xff"
 >>> b = "\xa0"
 >>> ord(a) + ord(b)
415

HTH, Diez

Sorry I was not clear enough. When I said "add", I meant concatenate
because I want to read 0x0588 as one value and ord() does not allow
that.

(ord(a) << 8) + ord(b)


Diez
--
http://mail.python.org/mailman/listinfo/python-list

Reply via email to