Python int to binary string?

Question

Are there any canned Python methods to convert an Integer (or Long) into a binary string in Python?

There are a myriad of dec2bin() functions out on Google... But I

Answer 1

If you want a textual representation without the 0b-prefix, you could use this:

get_bin = lambda x: format(x, 'b')

print(get_bin(3))
>>> '11'

print(get_bin(-3))
>>> '-11'

When you want a n-bit representation:

get_bin = lambda x, n: format(x, 'b').zfill(n)
>>> get_bin(12, 32)
'00000000000000000000000000001100'
>>> get_bin(-12, 32)
'-00000000000000000000000000001100'

Alternatively, if you prefer having a function:

def get_bin(x, n=0):
    """
    Get the binary representation of x.

    Parameters
    ----------
    x : int
    n : int
        Minimum number of digits. If x needs less digits in binary, the rest
        is filled with zeros.

    Returns
    -------
    str
    """
    return format(x, 'b').zfill(n)