def getTimesAtLocation(self,stoploc,tol=10.0,starttime=None,findjustone=False):
"""
Given a (lat,lon), returns a list of (begin,end,dist) intervals of the
(estimated) times that the bus was within tol meters of that
location, starting at starttime. The 'dist' part of each interval
indicates the estimated minimum distance of the bus from stoploc during
that interval.
If starttime is None, then defaults to the beginning of the track.
If findjustone is True, returns after finding the first complete interval.
"""
in_range = False
current_interval = None # will be [begin,end,dist] holder
ret = []
if starttime is None: starttime = self.min_time;
starttime = max(starttime,self.min_time);
if starttime > self.max_time:
return ret
## Process intersection at first sub-segment
startloc = self.getLocationAtTime(starttime);
ll1 = startloc
ll2 = self.interpolation[self.cached_index+1][:2]
t1,t2 = starttime, self.interpolation[self.cached_index+1][2]
overall_min_dist = gis.distance_from_segment_meters( ll1, ll2, stoploc )
intersect = gis.distance_intersect( ll1, ll2, stoploc, tol )
if intersect:
enter_frac,exit_frac,min_dist = intersect
enter_time = gis.timefrac_helper( t1,t2,enter_frac )
exit_time = gis.timefrac_helper( t1,t2,exit_frac )
if exit_frac == 1.0:
current_interval = [ enter_time, exit_time, min_dist ]
in_range = True
else:
ret.append([ enter_time, exit_time, min_dist ])
## Process subsequent segments
for i in range(self.cached_index+1, len(self.interpolation)-1):
llt1 = self.interpolation[i]
llt2 = self.interpolation[i+1]
ll1,ll2 = llt1[:2],llt2[:2]
if len(ret) > 0 and findjustone:
return ret
overall_min_dist = min( overall_min_dist,
gis.distance_from_segment_meters(ll1,ll2,stoploc))
intersect = gis.distance_intersect( ll1,ll2,stoploc,tol )
if intersect is None:
if in_range:
ret.append(current_interval)
in_range = False
current_interval = None
else:
pass
else: # intersect is not None
enter_frac,exit_frac,min_dist = intersect
enter_time = gis.timefrac_helper( llt1[2],llt2[2],enter_frac )
exit_time = gis.timefrac_helper( llt1[2],llt2[2],exit_frac )
if not in_range: # just entered range of stoploc
if exit_frac == 1.0:
current_interval = [ enter_time, exit_time, min_dist ]
in_range = True
else:
ret.append([ enter_time, exit_time, min_dist ])
else: # in_range
if enter_frac != 0.0:
raise Exception, "While in range, found enter_frac of %f" % (enter_frac,)
else:
current_interval[1] = exit_time
current_interval[2] = min(current_interval[2],min_dist)
if exit_frac == 1.0: # we're still in range
pass
else:
ret.append( current_interval )
in_range = False
current_interval = None
else: # end "for i in range..."
if in_range:
ret.append(current_interval)
if not ret: # empty list
print "--- No arrival, min dist was:",overall_min_dist
return ret
def getTimesAtLocation(self,
stoploc,
tol=10.0,
starttime=None,
findjustone=False):
"""
Given a (lat,lon), returns a list of (begin,end,dist) intervals of the
(estimated) times that the bus was within tol meters of that
location, starting at starttime. The 'dist' part of each interval
indicates the estimated minimum distance of the bus from stoploc during
that interval.
If starttime is None, then defaults to the beginning of the track.
If findjustone is True, returns after finding the first complete interval.
"""
in_range = False
current_interval = None # will be [begin,end,dist] holder
ret = []
if starttime is None: starttime = self.min_time
starttime = max(starttime, self.min_time)
if starttime > self.max_time:
return ret
## Process intersection at first sub-segment
startloc = self.getLocationAtTime(starttime)
ll1 = startloc
ll2 = self.interpolation[self.cached_index + 1][:2]
t1, t2 = starttime, self.interpolation[self.cached_index + 1][2]
overall_min_dist = gis.distance_from_segment_meters(ll1, ll2, stoploc)
intersect = gis.distance_intersect(ll1, ll2, stoploc, tol)
if intersect:
enter_frac, exit_frac, min_dist = intersect
enter_time = gis.timefrac_helper(t1, t2, enter_frac)
exit_time = gis.timefrac_helper(t1, t2, exit_frac)
if exit_frac == 1.0:
current_interval = [enter_time, exit_time, min_dist]
in_range = True
else:
ret.append([enter_time, exit_time, min_dist])
## Process subsequent segments
for i in range(self.cached_index + 1, len(self.interpolation) - 1):
llt1 = self.interpolation[i]
llt2 = self.interpolation[i + 1]
ll1, ll2 = llt1[:2], llt2[:2]
if len(ret) > 0 and findjustone:
return ret
overall_min_dist = min(
overall_min_dist,
gis.distance_from_segment_meters(ll1, ll2, stoploc))
intersect = gis.distance_intersect(ll1, ll2, stoploc, tol)
if intersect is None:
if in_range:
ret.append(current_interval)
in_range = False
current_interval = None
else:
pass
else: # intersect is not None
enter_frac, exit_frac, min_dist = intersect
enter_time = gis.timefrac_helper(llt1[2], llt2[2], enter_frac)
exit_time = gis.timefrac_helper(llt1[2], llt2[2], exit_frac)
if not in_range: # just entered range of stoploc
if exit_frac == 1.0:
current_interval = [enter_time, exit_time, min_dist]
in_range = True
else:
ret.append([enter_time, exit_time, min_dist])
else: # in_range
if enter_frac != 0.0:
raise Exception, "While in range, found enter_frac of %f" % (
enter_frac, )
else:
current_interval[1] = exit_time
current_interval[2] = min(current_interval[2],
min_dist)
if exit_frac == 1.0: # we're still in range
pass
else:
ret.append(current_interval)
in_range = False
current_interval = None
else: # end "for i in range..."
if in_range:
ret.append(current_interval)
if not ret: # empty list
print "--- No arrival, min dist was:", overall_min_dist
return ret
def getArrivalTimeAtLocation(self,stoploc,tol=10.0,starttime=None):
"""
Given a stop location (lat,lon), a tolerance in meters, and a starting
time, does the following:
Finds the first time interval (t1,t2) within which the line segments
of this track are all within tol meters of stoploc, and t1>starttime.
Returns the time t such that t1<=t<=t2 at which this track was closest
to stoploc.
If this track was never within tol meters of the location, then
returns None.
"""
## We'll use the internal cached index here, just as in the
## getLocationAtTime method, in order to speed up sequential
## requests to this method.
# Some might consider this bad programming practice,
# in that we rely on the behavior of another method
# to correcty implement this one.
# If this ends up causing breakage, then there should
# be some kind of "setInternalTime()" method for this class.
if starttime is None: starttime = self.min_time;
starttime = max(starttime,self.min_time);
if starttime > self.max_time:
return None
startloc = self.getLocationAtTime(starttime);
ll1 = startloc
ll2 = self.interpolation[self.cached_index+1][:2]
min_dist,frac = gis.interp_helper(ll1,ll2,stoploc);
min_time = gis.timefrac_helper(starttime,
self.interpolation[self.cached_index+1][2],
frac);
within_tol = (min_dist < tol);
if str(min_time) == 'nan':
raise Exception, "WTF"
for idx in range(self.cached_index+1, len(self.interpolation)-1):
pt1 = self.interpolation[idx];
pt2 = self.interpolation[idx+1];
ll1 = pt1[:2]
ll2 = pt2[:2]
dist,frac = gis.interp_helper(ll1,ll2,stoploc);
if dist < min_dist:
min_dist = dist;
min_time = gis.timefrac_helper(pt1[2],pt2[2],frac);
if str(min_time) == 'nan':
raise Exception, "WTF"
if (dist > tol) and within_tol:
#We've left the tolerance zone, so we should have an answer
break
if (dist > tol):
# We haven't found the tolerance zone yet
continue
within_tol = True;
if not within_tol:
# We never entered a tolerance zone
print "XXX No arrival, min dist was:",min_dist
return None
print "OOO Arrival with distance:",min_dist
return min_time
def getArrivalTimeAtLocation(self, stoploc, tol=10.0, starttime=None):
"""
Given a stop location (lat,lon), a tolerance in meters, and a starting
time, does the following:
Finds the first time interval (t1,t2) within which the line segments
of this track are all within tol meters of stoploc, and t1>starttime.
Returns the time t such that t1<=t<=t2 at which this track was closest
to stoploc.
If this track was never within tol meters of the location, then
returns None.
"""
## We'll use the internal cached index here, just as in the
## getLocationAtTime method, in order to speed up sequential
## requests to this method.
# Some might consider this bad programming practice,
# in that we rely on the behavior of another method
# to correcty implement this one.
# If this ends up causing breakage, then there should
# be some kind of "setInternalTime()" method for this class.
if starttime is None: starttime = self.min_time
starttime = max(starttime, self.min_time)
if starttime > self.max_time:
return None
startloc = self.getLocationAtTime(starttime)
ll1 = startloc
ll2 = self.interpolation[self.cached_index + 1][:2]
min_dist, frac = gis.interp_helper(ll1, ll2, stoploc)
min_time = gis.timefrac_helper(
starttime, self.interpolation[self.cached_index + 1][2], frac)
within_tol = (min_dist < tol)
if str(min_time) == 'nan':
raise Exception, "WTF"
for idx in range(self.cached_index + 1, len(self.interpolation) - 1):
pt1 = self.interpolation[idx]
pt2 = self.interpolation[idx + 1]
ll1 = pt1[:2]
ll2 = pt2[:2]
dist, frac = gis.interp_helper(ll1, ll2, stoploc)
if dist < min_dist:
min_dist = dist
min_time = gis.timefrac_helper(pt1[2], pt2[2], frac)
if str(min_time) == 'nan':
raise Exception, "WTF"
if (dist > tol) and within_tol:
#We've left the tolerance zone, so we should have an answer
break
if (dist > tol):
# We haven't found the tolerance zone yet
continue
within_tol = True
if not within_tol:
# We never entered a tolerance zone
print "XXX No arrival, min dist was:", min_dist
return None
print "OOO Arrival with distance:", min_dist
return min_time