def process(self): """A trip has just ended. What do we do with it?""" # As this may be being REprocessed we need to clean up any traces of the # result of earlier processing so that we have a fresh start db.scrub_trip(self.trip_id) # see if we have enough stuff to bother with if len(self.vehicles) < 5: # km return db.ignore_trip(self.trip_id,'too few vehicles') # calculate vector of segment speeds self.segment_speeds = self.get_segment_speeds() # check for very short trips if self.length < 0.8: # km return db.ignore_trip(self.trip_id,'too short') # check for errors and attempt to correct them while self.has_errors(): # make sure it's still long enough to bother with if len(self.vehicles) < 5: return db.ignore_trip(self.trip_id,'processing made too short') # still long enough to try fixing self.fix_error() # update the segment speeds for the next iteration self.segment_speeds = self.get_segment_speeds() # trip is clean, so store the cleaned line db.set_trip_clean_geom( self.trip_id, dumpWKB( self.get_geom(), hex=True ) ) # get the stops (as a list of Stop objects) self.stops = db.get_stops(self.direction_id,self.last_seen) # and begin matching self.map_match_trip() if not self.match.is_useable: return db.ignore_trip(self.trip_id,'match problem') self.interpolate_stop_times()
def process(self):
"""A trip has just ended. What do we do with it?"""
# As this may be being REprocessed we need to clean up any traces of the
# result of earlier processing so that we have a fresh start
db.scrub_trip(self.trip_id)
# see if we have enough stuff to bother with
if len(self.vehicles) < 5: # km
return db.ignore_trip(self.trip_id, 'too few vehicles')
# calculate vector of segment speeds
self.segment_speeds = self.get_segment_speeds()
# check for very short trips
if self.length < 0.8: # km
return db.ignore_trip(self.trip_id, 'too short')
# check for errors and attempt to correct them
while self.has_errors():
# make sure it's still long enough to bother with
if len(self.vehicles) < 5:
return db.ignore_trip(self.trip_id,
'processing made too short')
# still long enough to try fixing
self.fix_error()
# update the segment speeds for the next iteration
self.segment_speeds = self.get_segment_speeds()
# trip is clean, so store the cleaned line
db.set_trip_clean_geom(self.trip_id, dumpWKB(self.get_geom(),
hex=True))
# and begin matching
self.map_match_trip()
if len(self.vehicles) == 0:
return db.ignore_trip(
self.trip_id, 'too many vehicles removed during measurement')
self.interpolate_stop_times()
def get_geom(self):
"""return a clean WKB geometry string using all vehicles
in the local projection"""
line = []
for v in self.vehicles:
line.append(v['geom'])
return dumpWKB(LineString(line), hex=True)
def save(self):
"""Store a record of this trip in the DB. This allows us to
reprocess as from the beginning with different parameters,
data, etc. GPS points are stored as an array of times and
a linestring. This function is to be called just before
process() as data is being collected."""
times = []
for v in self.vehicles:
times.append(v.time)
db.insert_trip(self.trip_id, self.block_id, self.route_id,
self.direction_id, self.vehicle_id, times,
dumpWKB(self.get_geom(), hex=True))
def map_match_trip(self):
"""1) Match the trip GPS points to the road network, id est, improve
the spatial accuracy of the trip.
2) Get the location/measure of stops and vehicles along the path.
4) Interpolate sequence of stop_times from vehicle times."""
# create a match object, passing it this trip to get it started
self.match = map_api.match(self)
if not self.match.is_useable:
return db.ignore_trip(self.trip_id, 'match problem')
# store the match info and geom in the DB
db.add_trip_match(self.trip_id, self.match.confidence,
dumpWKB(self.match.geometry, hex=True))
# find the measure of the vehicles for time interpolation
self.match.locate_vehicles_on_route()
def map_match_trip(self): """Match the trip GPS points to the road network, ie, improve the spatial accuracy of the trip. Get the location/measure of stops and vehicles along the path.""" # create a match object, passing it this trip to get it started self.match = map_api.match(self) if not self.match.is_useable: return db.ignore_trip(self.trip_id,'match problem') # store the match info and geom in the DB db.add_trip_match( self.trip_id, self.match.confidence, dumpWKB(self.match.geometry,hex=True) )
def save(self): """Store a record of this trip in the DB. This allows us to reprocess as from the beginning with different parameters, data, etc. GPS points are stored as an array of times and a linestring. This function is to be called just before process() as data is being collected.""" db.insert_trip( self.trip_id, self.block_id, self.route_id, self.direction_id, self.vehicle_id, [ v.time for v in self.vehicles ], dumpWKB( self.get_geom(), hex=True ) )
dest = random_point(zones[trip_dest])
# create and send the request
response = requests.get('http://localhost:5000/route/v1/bicycle/' +
str(orig.x) + ',' + str(orig.y) + ';' +
str(dest.x) + ',' + str(dest.y),
params=options,
timeout=1)
# parse the output
j = json.loads(response.text)
if j['code'] != 'Ok':
print(response.text, '\n')
continue
# good respone - now parse and store it
results = {}
results['uid'] = trip_uid
results['network_distance'] = j['routes'][0]['distance']
results['orig_geom'] = dumpWKB(orig)
results['dest_geom'] = dumpWKB(dest)
results['path_geom'] = dumpWKB(asShape(j['routes'][0]['geometry']))
cursor2.execute(
"""
UPDATE syn_trips SET
network_trip_distance = %(network_distance)s,
orig_geog = %(orig_geom)s::geography,
dest_geog = %(dest_geom)s::geography,
network_trip_geog = %(path_geom)s::geography
WHERE uid = %(uid)s;
""", results)
edgeB.forward_count * edgeB.geometry.length
) / newGeom.length )
new_reverse_count = round( (
edgeA.reverse_count * edgeA.geometry.length +
edgeB.reverse_count * edgeB.geometry.length
) / newGeom.length )
# delete the first edge and update the second one
edge_cursor.execute("""
UPDATE street_edges SET
node_1 = %(node_1)s,
node_2 = %(node_2)s,
r = %(r)s,
f = %(f)s,
edge = ST_SetSRID(%(geom)s::geometry,3857),
renovated = TRUE
WHERE uid = %(edge1id)s;
DELETE FROM street_edges WHERE uid = %(edge2id)s;
""",{
'edge1id':edgeA.db_uid,
'edge2id':edgeB.db_uid,
'node_1': new_from_id,
'node_2': new_to_id,
'f':new_forward_count,
'r':new_reverse_count,
'geom': dumpWKB( newGeom, hex=True )
})
connection.commit()
def match(self):
"""Match the trip to the road network, and do all the
things that follow therefrom."""
match = map_api.match(self.vehicles)
if not match.is_useable:
return db.ignore_trip(self.trip_id, 'match problem')
self.match_confidence = match.confidence
# store the trip geometry
self.match_geom = match.geometry()
# and reproject it
self.match_geom = reproject(conf['projection'], self.match_geom)
# simplify slightly for speed (2 meter simplification)
self.match_geom = self.match_geom.simplify(2)
# if the multi actually just had one line, this simplifies to a
# linestring, which can cause problems down the road
if self.match_geom.geom_type == 'LineString':
self.match_geom = MultiLineString([self.match_geom])
# store the match info and geom in the DB
db.add_trip_match(self.trip_id, self.match_confidence,
dumpWKB(self.match_geom, hex=True))
# drop vehicles that did not contribute to the match
vehicles_used = match.vehicles_used()
for i in reversed(range(0, len(self.vehicles))):
if not vehicles_used[i]: del self.vehicles[i]
# get distances of each vehicle along the match geom
for vehicle, cum_dist in zip(self.vehicles, match.cum_distances()):
vehicle['cum_dist'] = cum_dist
# However, because we've simplified the line, the distances will be slightly off
# and need correcting
adjust_factor = self.match_geom.length / self.vehicles[-1]['cum_dist']
for v in self.vehicles:
v['cum_dist'] = v['cum_dist'] * adjust_factor
# get the stops as a list of objects
# with keys {'id':stop_id,'g':geom}
self.stops = db.get_stops(self.direction_id, self.last_seen)
# process the geoms
for stop in self.stops:
stop['geom'] = loadWKB(stop['geom'], hex=True)
# now match stops to the trip geometry, 750m at a time
path = self.match_geom
traversed = 0
# while there is more than 750m of path remaining
while path.length > 0:
subpath, path = cut(path, 750)
# check for nearby stops
for stop in self.stops:
# if the stop is close enough
stop_dist = subpath.distance(stop['geom'])
if stop_dist <= conf['stop_dist']:
# measure how far it is along the trip
measure = traversed + subpath.project(stop['geom'])
# add it to a list of possible stop times
self.add_arrival(stop['id'], measure, stop_dist)
# note what we have already traversed
traversed += 750
# sort stops by arrival time
self.timepoints = sorted(self.timepoints, key=lambda k: k['time'])
# there is more than one stop, right?
if len(self.timepoints) > 1:
# store the stop times
db.store_timepoints(self.trip_id, self.timepoints)
# Now set the service_id, which is the (local) DAY equivalent of
# the unix epoch, which is centered on Greenwich.
# (The service_id is distinct to a day in the local timezone)
# First, shift the second_based epoch to local time
tlocal = self.timepoints[0]['time'] + conf['timezone'] * 3600
# then find the "epoch day"
service_id = math.floor(tlocal / (24 * 3600))
# and store it in the DB
db.set_service_id(self.trip_id, service_id)
else:
db.ignore_trip(self.trip_id, 'one or fewer timepoints')
return
