Ejemplo n.º 1
0
def raw_group(divisors,messages,qh,rh,wh):
	'''
	purpose
		return a group with:
			name: 'crc_d%i_m%i_' with divisor, message lengths
			divisors: a list of divisors of the same length
			messages: a list of messages of the same length
			forward only: no divisor or dividend hotspots
			quotient hotspots: list of all qh-tuples of hotspots
			remainder hotspots: list of all rh-tuples of hotspots
			work hotspots: list of all rh-tuples of hotspots
	preconditions
		divisors: non-empty list of bitstrings of length > 1
			all divisors are the same length
		messages: non-empty list of bitstrings of length >= d
			all messages are the same length
		qh, rh, wh: legal hotspot counts
	'''
	# extract divisor, message lengths
	d_len = len(divisors[0])
	m_len = len(messages[0])

	# compute quotient, remainder, work lengths
	q_len = crc_util.quotient_len(d_len,m_len)
	r_len = crc_util.remainder_len(d_len,m_len)
	num_rows = crc_util.number_of_rows(d_len,m_len)
	row_width = crc_util.row_width(d_len,m_len)

	# compute quotient, remainder, work index lists; index pairs for work
	q_indexes = range(0,q_len)
	r_indexes = range(0,r_len)
	w_indexes = generate_util.cross_product \
		([range(num_rows),range(row_width)])

	# create the group, ready for cross product
	return [ 'crc_d%i_m%i_' % (d_len,m_len), [
		divisors, messages, [ ], [ ],
		generate_util.choose_k(q_indexes,qh),
		generate_util.choose_k(r_indexes,rh),
		generate_util.choose_k(w_indexes,wh),
	]]
Ejemplo n.º 2
0
def raw_group_num_questions(divisors,messages,qh,rh,wh):
	'''
	purpose, preconditions, comments
		same as for group_count except that the number of questions
		generated by the return value of raw_group is returned
	'''
	d_len = len(divisors[0])
	m_len = len(messages[0])

	q_len = crc_util.quotient_len(d_len,m_len)
	r_len = crc_util.remainder_len(d_len,m_len)
	num_rows = crc_util.number_of_rows(d_len,m_len)
	row_width = crc_util.row_width(d_len,m_len)

	q_indexes = range(0,q_len)
	r_indexes = range(0,r_len)
	w_indexes = generate_util.cross_product \
		([range(num_rows),range(row_width)])

	return len(divisors) * len(messages) * \
		generate_util.n_c_k(q_len,qh) * \
		generate_util.n_c_k(r_len,rh) * \
		generate_util.n_c_k(num_rows*row_width,wh)