Ascii to binary conversion

[azrael]

looks nice. is there an oposite function of ord() so I could also
bring a binary number also back to ascii.

the speed matters if you plan to exchange about 10 M ascii chars and
don't wont to wait a year for the results. :)



On 9 kol, 15:39, John Machin <sjmac... at lexicon.net> wrote:
> On Aug 9, 11:18 pm, azrael <jura.gro... at gmail.com> wrote:
>
> > Hy folks,
>
> > I googled, and searched, and can not bealive that I have not found a
> > built in way to convert the easy and elegant python way a function to
> > easily convert simple ascii data to binary and back.
>
> > I've written some my own but they were pretty slow using binascii
> > linbrary with hexifly and unhexifly functions conbined with a
> > lookuptable of binary and hex values.
>
> > Any idea how to easily write a function that recieves a character or
> > string and returns a binary number like:
> > ascii("1") is converted to bin("00110001")
>
> Here's one way:
>
> >>> def a2b(a):
>
> ...    ai = ord(a)
> ...    return ''.join('01'[(ai >> x) & 1] for x in xrange(7, -1, -1))
> ...
>
> >>> a2b('1')
> '00110001'
> >>> a2b('2')
> '00110010'
> >>> a2b(chr(0))
> '00000000'
> >>> a2b(chr(255))
> '11111111'
>
> BUT ... why are you doing this so much that the speed matters???