fperez528 at yahoo
May 2, 2003, 1:13 PM
Post #2 of 9
(1048 views)
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ekranawetter-piber wrote:
> Hi all,
>
> I couldn't find any function in Python to convert integers to binary
> and vice versa, for example:
>
> integer 16 = bin 10000, or
> integer 15 = bin 1111
> bin 11 = integer 3
These are pulled from by bitbucket. I don't claim credit for them, as it's
quite possible that they are reworks of code I found on the net:
def base_repr (number, base = 2, padding = 0):
"""Return the representation of a number in any given base."""
chars = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'
if number < base: \
return (padding - 1) * chars [0] + chars [int (number)]
max_exponent = int (math.log (number)/math.log (base))
max_power = long (base) ** max_exponent
lead_digit = int (number/max_power)
return chars [lead_digit] + \
base_repr (number - max_power * lead_digit, base, \
max (padding - 1, max_exponent))
def binary_repr (number, max_length = 64):
"""Return the binary representation of the input number as a string.
This is more efficient than using base_repr with base 2.
This will only work reliably for relatively small numbers.
Increase the value of max_length if you think you're going
to use long integers."""
assert number < 2L << max_length
shifts = map (operator.rshift, max_length * [number], \
range (max_length - 1, -1, -1))
digits = map (operator.mod, shifts, max_length * [2])
if not digits.count (1): return 0
digits = digits [digits.index (1):]
return ''.join (map (repr, digits)).replace('L','')
def bin(i):
"""Return the binary representation of the input number as a string.
Efficient, but returns leading zeros."""
l = [.'0000', '0001', '0010', '0011', '0100', '0101', '0110', '0111',
'1000', '1001', '1010', '1011', '1100', '1101', '1110', '1111']
s = ''.join(map(lambda x: l[int(x, 16)], hex(i)[2:]))
if s[0] == '1' and i > 0:
s = '0000' + s
return s
>
> please help and send an email to this adress and
> ekranawetter [at] bmw
Cheers,
f.
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