class EventSequence(object):
"""
A class to collect a sequence of Event's ordered (increasing) by the Event's time value.
The class contains the following event accounting structures:
1) OrderedMap: ordering the events by time in a map that provides a floor() function.
2) successor: a dict that maps events to successors.
3) predecessor: a dict that maps events to predecessors.
4) first: first event in the event sequence.
5) last: last event in the event sequence.
"""
def __init__(self, event_list=None):
"""
Constructor.
Args:
event_list: Any of None, a single Event, or a list of Events.
"""
self.ordered_map = OrderedMap()
self._successor = {}
self._predecessor = {}
self.__first = None
self.__last = None
if event_list:
self.add(event_list)
@property
def sequence_list(self):
return list(self.ordered_map.get(x) for x in self.ordered_map.keys())
@property
def is_empty(self):
return self.ordered_map.is_empty()
def floor(self, time):
return self.ordered_map.floor(time)
def event(self, index):
return self.ordered_map.get(index)
def floor_event(self, time):
floor_position = self.floor(time)
return self.event(floor_position) if floor_position else None
@property
def first(self):
return self.__first
@property
def last(self):
return self.__last
def add(self, new_members):
"""
Add any of a single Event or a list of Events.
Args:
new_members: Any of a single Event or a list of events
"""
if isinstance(new_members, list):
mem_set = new_members
inputt = [(e.time, e) for e in new_members]
else:
mem_set = [new_members]
inputt = [(new_members.time, new_members)]
for m in mem_set:
if self.ordered_map.has_reverse(m):
raise Exception('{0} already a member of sequence.'.format(m))
if not isinstance(m, Event):
raise Exception('{0} is not an event.'.format(m))
for i in inputt:
if i[1].time not in self.ordered_map:
self._add_successor_predecessor_maps(i[1])
else:
self._update_successor_predecessor_maps(i[1])
self.ordered_map.insert(i[0], i[1])
def remove(self, members):
"""
Remove any of a single Event or a list of Events already in the sequence.
Args:
members: Any of a single Event or a list of Events already in the sequence.
"""
if isinstance(members, list):
for member in members:
self.remove(member)
else:
if not self.ordered_map.has_reverse(members):
raise Exception('{0} not a member of sequence'.format(members))
self._remove_successor_predecessor_maps(members)
self.ordered_map.remove_key(self.ordered_map.reverse_get(members))
def move_event(self, event, new_time):
"""
Method to move event in sequence to a new time.
Args:
event: (Event) to move
new_time: the new time setting for the event
"""
if self.event(event.time) != event:
raise Exception('Given event at time {0} not in sequence'.format(event.time))
self.remove(event)
event.time = new_time
self.add(event)
def _add_successor_predecessor_maps(self, event):
fl_key = self.floor(event.time)
if fl_key:
a = self.event(fl_key)
b = self._successor[a] # could be None event is between a and b
self._successor[a] = event
self._successor[event] = b
self._predecessor[event] = a
if b:
self._predecessor[b] = event
else:
self.__last = event
else: # this event has to come first
if self.__first:
self._successor[event] = self.__first
self._predecessor[self.__first] = event
self._predecessor[event] = None
self.__first = event
else:
self.__first = self.__last = event
self._successor[event] = None
self._predecessor[event] = None
def _update_successor_predecessor_maps(self, event):
e = self.event(event.time)
self.remove(e)
self._add_successor_predecessor_maps(event)
pass
def _remove_successor_predecessor_maps(self, event):
a = self._predecessor[event]
b = self._successor[event]
del self._successor[event]
del self._predecessor[event]
if a:
self._successor[a] = b
else:
self.__first = b
if b:
self._predecessor[b] = a
else:
self.__last = a
def clear(self):
self.ordered_map.clear()
self._successor.clear()
self._predecessor.clear()
def successor(self, event):
return self._successor[event] if event in self._successor else None
def predecessor(self, event):
return self._predecessor[event] if event in self._predecessor else None
def __str__(self):
return ', '.join(str(x) for x in self.sequence_list)
def print_maps(self):
print('---------')
if self.__first:
print('first={0}'.format(self.__first))
else:
print('first=None')
if self.__first:
print('last={0}'.format(self.__last))
else:
print('last=None')
print('Successor:')
for i in self._successor.items():
print(' {0} --> {1}'.format(i[0].object if i[0] else 'None', i[1].object if i[1] else 'None'))
print('Predecessor:')
for i in self._predecessor.items():
print(' {0} --> {1}'.format(i[0].object if i[0] else 'None', i[1].object if i[1] else 'None'))
class HarmonicContextTrack(object):
def __init__(self):
"""
Constructor.
"""
self.ordered_map = OrderedMap()
self._wnt_duration = Duration(0)
def __getitem__(self, position):
"""
Get the harmonic context based on the floor of the given position.
:param position:
:return:
"""
floor_position = self.ordered_map.floor(position)
return None if floor_position is None else self.ordered_map[
floor_position]
def __len__(self):
return len(self.ordered_map)
@property
def duration(self):
return self._wnt_duration
def hc_list(self):
return [self.ordered_map[hc] for hc in self.ordered_map.keys()]
def reset(self):
self._reset_hc_list(self.ordered_map.value_items())
def append(self, harmonic_context):
"""
Append a harmonic context to the end of the track.
It is recommended to use this call to build the track, as the key data members are not rebuilt.
:param harmonic_context:
:return:
"""
last_hc = None if self.ordered_map.is_empty(
) else self.ordered_map.value_items()[-1]
harmonic_context.position = Position(
0) if last_hc is None else last_hc.position + last_hc.duration
self.ordered_map.insert(harmonic_context.position, harmonic_context)
self._wnt_duration += harmonic_context.duration.duration
def append_first(self, harmonic_context):
"""
Append a harmonic context to the beginning of the track, and shove right all existing HC's
by the duration of the added HC.
:param harmonic_context:
:return:
"""
hc_list = self.ordered_map.value_items()
hc_list.insert(0, harmonic_context)
self._reset_hc_list(hc_list)
def insert(self, position_key, harmonic_context):
"""
Insert a harmonic context at a given position. The insertion happens after the HC that is floor(position_key).
:param position_key:
:param harmonic_context:
:return:
"""
hc_list = self.ordered_map.value_items()
hc_target_index = self.ordered_map.floor(position_key)
index = 0 if hc_target_index is None else hc_list.index(
self.ordered_map[hc_target_index])
hc_list.insert(index, harmonic_context)
harmonic_context.position = position_key
self._reset_hc_list(hc_list)
def get_hc_by_position(self, position):
return self.ordered_map[self.ordered_map.floor(position)]
def replace(self, position_key, harmonic_context):
if position_key not in self.ordered_map:
raise Exception(
'Attempt to replace a harmonic context with invalid key')
harmonic_context.position = position_key
self.ordered_map.insert(position_key, harmonic_context)
self._reset_hc_list(self.ordered_map.value_items())
def remove(self, harmonic_context):
"""
Remove the given harmonic content. Error if it does not exist.
:param harmonic_context:
:return:
"""
if harmonic_context.position not in self.ordered_map or \
self.ordered_map[harmonic_context.position] != harmonic_context:
raise Exception(
'Attempt of remove harmonic context that is not in list')
self.ordered_map.remove_key(harmonic_context.position)
self._reset_hc_list(self.ordered_map.value_items())
def _reset_hc_list(self, hc_list):
p = Position(0)
new_ordered_map = OrderedMap()
for hc in hc_list:
hc.position = p
new_ordered_map.insert(p, hc)
p += hc.duration
self.ordered_map = new_ordered_map
self._wnt_duration = Duration(p.position)
def clear(self):
self.ordered_map = OrderedMap()
self._wnt_duration = Duration(0)
def __str__(self):
l = self.hc_list()
return '\n'.join('[{0}] {1}'.format(i, str(l[i]))
for i in range(0, len(self)))
def sub_hct(self, sub_track_interval=None):
"""
Take a sub_track of this hct.
:param sub_track_interval: NmericInterval. If none, the entire hct.
:return:
"""
sub_track_interval = NumericInterval(Fraction(0), self.duration.duration) if sub_track_interval is None else \
sub_track_interval
new_track = HarmonicContextTrack()
for hc in self.hc_list():
hc_interval = NumericInterval(
hc.position.position,
hc.position.position + hc.duration.duration)
hc_intersect = hc_interval.intersection(sub_track_interval)
if hc_intersect is not None:
new_hc = HarmonicContext(hc.tonality, hc.chord,
Duration(hc_intersect.length()),
Position(hc_intersect.lower))
new_track.append(new_hc)
return new_track
def reverse(self):
new_track = HarmonicContextTrack()
offset = Position(0)
for hc in reversed(self.hc_list()):
hs_prime = HarmonicContext(hc.tonality, hc.chord, hc.duration,
offset)
new_track.append(hs_prime)
offset = offset + hc.duration
return new_track