csong@1: '''
csong@1: Author: Chunyang Song
csong@1: Institution: Centre for Digital Music, Queen Mary University of London
csong@1: 
csong@1: '''
csong@1: 
csong@1: from basic_functions import ceiling, find_divisor, get_min_timeSpan
csong@1: 
csong@1: # This function calculates the syncopation value for TOB model.
csong@1: def get_syncopation(seq):
csong@1: 	syncopation = 0
csong@1: 	bseq_ts = get_min_timeSpan(ceiling(seq))	# converting to binary and mininum time-span sequence
csong@1: 	divisors = find_divisor(len(bseq_ts))		# find all the divisors other than 1 and the length of this sequence
csong@1: 	del divisors[0]
csong@1: 	del divisors[-1]
csong@1: 
csong@1: 	offbeatness = [1]*len(bseq_ts)			
csong@1: 	for index in range(len(bseq_ts)):
csong@1: 		for d in divisors:
csong@1: 			if index % d == 0:
csong@1: 				offbeatness[index] = 0
csong@1: 				break
csong@1: 		syncopation += bseq_ts[index]*offbeatness[index]
csong@1: 	return syncopation