comparison Syncopation models/LHL.py @ 28:5de1cb45c145

Parameters setting implemented.

 Author: Chunyang Song
 Institution: Centre for Digital Music, Queen Mary University of London
 '''
 
 from basic_functions import concatenate, repeat, subdivide, ceiling, get_rhythm_category
+from parameter_setter import are_parameters_valid
 
 terminalNodes = []		# Global variable, storing all the terminal nodes from recursive tree structure in time order
 
 # Each terminnal node contains two properties: its node type (note or rest) and its metrical weight.
 class Node:

 		subBinarySequences = subdivide(binarySequence, subdivisionSequence[level+1])	
 		subWeightSequences = concatenate([metricalWeight],repeat([weightSequence[level+1]],subdivisionSequence[level+1]-1))
 		for a in range(len(subBinarySequences)):
 			recursive_tree(subBinarySequences[a], subdivisionSequence, weightSequence, subWeightSequences[a], level+1)
 
-#!!!! needs fixing
-def are_parameters_valid(parameters):
-	areValid = True
-#	if 'Lmax' not in parameters :
 
 def get_syncopation(bar, parameters = None):
 	del terminalNodes[:]
 	syncopation = None
 
 	binarySequence = bar.get_binary_sequence()
 	subdivisionSequence = bar.get_subdivision_sequence()
 
+	# LHL can only measure monorhythms
 	if get_rhythm_category(binarySequence, subdivisionSequence) == 'poly':
 		print 'Warning: LHL model detects polyrhythms so returning None.'
 	else:
-		# If the parameters are not given, use the default settings
-		if parameters == None:
-			Lmax  = 5
-			weightSequence = range(0,-Lmax,-1) # i.e. [0,-1,-2,-3,-4]
+		# set defaults
+		Lmax = 5
+		weightSequence = range(0,-Lmax,-1)
+		# if parameters are specified by users, check their validities and update parameters if valid		
+		if parameters!= None:
+			if 'Lmax' in parameters:
+				Lmax = parameters['Lmax']				
+			if 'W' in parameters:
+				weightSequence = parameters['W']
+
+		if not are_parameters_valid(Lmax, weightSequence, subdivisionSequence):
+			print 'Error: the given parameters are not valid.'
 		else:
-			if are_parameters_valid(parameters):
-				Lmax = parameters['Lmax']
-				weightSequence = parameters['W']
-			else:
-				pass
-				#raise InvalidParameterError
+			# If there is rhythm in previous bar, process its tree structure
+			if bar.get_previous_bar() != None:
+				prebarBinarySequence = bar.get_previous_bar().get_binary_sequence()
+				recursive_tree(ceiling(prebarBinarySequence), subdivisionSequence, weightSequence, weightSequence[0],0)
+				
+				# Only keep the last note-type node
+				while terminalNodes[-1].nodeType != 'N':
+					del terminalNodes[-1]
+				del terminalNodes[0:-1]
 
-		# If there is rhythm in previous bar, process its tree structure
-		if bar.get_previous_bar() != None:
-			prebarBinarySequence = bar.get_previous_bar().get_binary_sequence()
-			recursive_tree(ceiling(prebarBinarySequence), subdivisionSequence, weightSequence, weightSequence[0],0)
+			# For the rhythm in the current bar, process its tree structure and store the terminal nodes 
+			recursive_tree(ceiling(binarySequence), subdivisionSequence, weightSequence, weightSequence[0],0)
 			
-			# Only keep the last note-type node
-			while terminalNodes[-1].nodeType != 'N':
-				del terminalNodes[-1]
-			del terminalNodes[0:-1]
+			# for t in terminalNodes:
+			# 	print '<', t.nodeType, t.metricalWeight, '>'
 
-		# For the rhythm in the current bar, process its tree structure and store the terminal nodes 
-		recursive_tree(ceiling(binarySequence), subdivisionSequence, weightSequence, weightSequence[0],0)
-		
-		# for t in terminalNodes:
-		# 	print '<', t.nodeType, t.metricalWeight, '>'
+			# Search for the NR pairs that contribute to syncopation,then add the weight-difference to the NRpairSyncopation list
+			NRpairSyncopation = []
+			for i in range(len(terminalNodes)-1,0,-1):
+				if terminalNodes[i].nodeType == 'R':
+					for j in range(i-1, -1, -1):
+						if (terminalNodes[j].nodeType == 'N') & (terminalNodes[i].metricalWeight >= terminalNodes[j].metricalWeight):
+							NRpairSyncopation.append(terminalNodes[i].metricalWeight - terminalNodes[j].metricalWeight)
+							break
+			#print NRpairSyncopation
 
-		# Search for the NR pairs that contribute to syncopation, 
-		# then add the weight-difference to the NRpairSyncopation list
-		NRpairSyncopation = []
-		for i in range(len(terminalNodes)-1,0,-1):
-			if terminalNodes[i].nodeType == 'R':
-				for j in range(i-1, -1, -1):
-					if (terminalNodes[j].nodeType == 'N') & (terminalNodes[i].metricalWeight >= terminalNodes[j].metricalWeight):
-						NRpairSyncopation.append(terminalNodes[i].metricalWeight - terminalNodes[j].metricalWeight)
-						break
-		#print NRpairSyncopation
-
-		# If there are syncopation, sum all the local syncopation values stored in NRpairSyncopation list	
-		if len(NRpairSyncopation) != 0:
-			syncopation = sum(NRpairSyncopation)
-		# If no syncopation, the value is -1; 	
-		elif len(terminalNodes) != 0:
-			syncopation = -1
+			# If there are syncopation, sum all the local syncopation values stored in NRpairSyncopation list	
+			if len(NRpairSyncopation) != 0:
+				syncopation = sum(NRpairSyncopation)
+			# If no syncopation, the value is -1; 	
+			elif len(terminalNodes) != 0:
+				syncopation = -1
 
 	return syncopation