PT_I-Übung 1

uebung1.py

#encoding: utf-8

from string import digits, ascii_uppercase

def base(b, n, symbols=digits+ascii_uppercase):
	'return the nubmer `n` with base `b`'
	if b > len(symbols):
		raise IndexError('Not enough symbols to represent base')

	digits = []
	while True:
		q, r = divmod(n, b)
		digits.append(symbols[r])
		n = q
		if n == 0:
			break
	return ''.join(reversed(digits))


def complement(b, number, bits):
	#in range?
	if not (-b**(bits-1) <= number < b**(bits-1)):
		raise IndexError('Number not representable with %s bits' %bits)
	
	if number < 0:
		return base(b, b**bits+number) #it's +number, since the number is negative
	else:
		return '{0:0>{bits}}'.format(base(b, number), bits=bits)


if __name__ == '__main__':

	import sys
	from jinja2 import Template
	
	text = u'''Aufgabe c:
{% for n in [62, 1000, 1024, 100000, 1048576] %}
	{{n}}
	{% for b, bname in ((2, 'Binärsystem'), (8, 'Oktalsystem'), (16, 'Hexadezimalsystem'), (11, 'Basis 11')) %}{{bname}}: {{base(b, n)}}
	{% endfor %}
{% endfor %}

Aufgabe d:
{% for n in -1, 1, 28, -35, -256, 257 %}	({{n}})
		Base2 -> {{complement(2, n, 16)}}
		Base16 -> {{complement(16, n, 16//4)}}
{% endfor %}

Aufgabe e:
	{% for u in 'Æ', '£', '\u03c1', '\u2264' %} {{u}}: {{ord(u)}}
	{% endfor %}'''

	print Template(text).render(
			base=base, ord=ord, complement=complement
			).encode('utf-8')