Binary digits: Difference between revisions

===String.format() method===

===Built-in bin() function===

===Custom functions===

Defined in terms of a more general '''showIntAtBase''' function:

<lang python>'''Binary strings for integers'''

# showBinary :: Int -> String

def showBinary(n):

'''Binary string representation of an integer.'''

def binaryChar(n):

return '1' if n != 0 else '0'

return showIntAtBase(2)(binaryChar)(n)('')

# TEST -------------------------------------------------

# main :: IO()

def main():

'''Test'''

print(unlines(

map(showBinary, enumFromTo(0)(16))

))

# GENERIC -------------------------------------------------

# enumFromTo :: (Int, Int) -> [Int]

def enumFromTo(m):

'''Integer enumeration from m to n.'''

return lambda n: list(range(m, 1 + n))

# showIntAtBase :: Int -> (Int -> String) -> Int -> String -> String

def showIntAtBase(base):

'''String representing a non-negative integer

using the base specified by the first argument,

and the character representation specified by the second.

The final argument is a (possibly empty) string to which

the numeric string will be prepended.'''

def wrap(toChr, n, rs):

def go(nd, r):

n, d = nd

r_ = toChr(d) + r

return go(divmod(n, base), r_) if 0 != n else r_

return 'unsupported base' if 1 >= base else (

'negative number' if 0 > n else (

go(divmod(n, base), rs))

)

return lambda toChr: lambda n: lambda rs: (

wrap(toChr, n, rs)

)

# unlines :: [String] -> String

def unlines(xs):

'''A single string derived by the intercalation

of a list of strings with the newline character.'''

return '\n'.join(xs)

if __name__ == '__main__':

main()</lang>