def _options_roads_neq( roadnet, road1, road2, length_attr ) :
edge1, data1 = ROAD.obtain_edge( roadnet, road1, data_flag=True )
u1,v1,_ = edge1 ; roadlen1 = data1.get( length_attr, np.inf )
edge2, data2 = ROAD.obtain_edge( roadnet, road2, data_flag=True )
u2,v2,_ = edge2 ; roadlen2 = data2.get( length_attr, np.inf )
x = GLOBAL.x ; y = GLOBAL.y
cost_dict = {
'<-s' : x,
's->' : roadlen1 - x,
'->t' : y,
't<-' : roadlen2 - y
}
options = []
# paths through endpoints
WAYP1 = [ ( 's->', v1 ) ]
if not data1.get( 'oneway', False ) : WAYP1.append( ( '<-s', u1 ) )
WAYP2 = [ ( '->t', u2 ) ]
if not data2.get( 'oneway', False ) : WAYP2.append( ( 't<-', v2 ) )
for s,u in WAYP1 :
p = ROAD.roadify( roadnet, u, length_attr )
for t,v in WAYP2 :
q = ROAD.roadify( roadnet, v, length_attr )
dst = ROAD.distance( roadnet, p, q, length_attr )
cost = cost_dict[s] + dst + cost_dict[t]
options.append( cost )
return options
def roadEd_conditional( roadnet, road1, road2, length_attr='length' ) :
edge1, data1 = ROAD.obtain_edge( roadnet, road1, data_flag=True )
roadlen1 = data1.get( length_attr, np.inf )
edge2, data2 = ROAD.obtain_edge( roadnet, road2, data_flag=True )
roadlen2 = data2.get( length_attr, np.inf )
phases = _compute_phases( roadnet, road1, road2, length_attr='length' )
pglints = [ _phase_to_pglint( c, constr ) for c,constr in phases ]
# somewhere we need to normalize!
vals = [ pglint.integrate( c, d, A, b ) for c, d, A, b in pglints ]
return sum( vals ) / roadlen1 / roadlen2
def _compute_phases( roadnet, road1, road2, length_attr ) :
edge1, data1 = ROAD.obtain_edge( roadnet, road1, data_flag=True )
roadlen1 = data1.get( length_attr, np.inf )
edge2, data2 = ROAD.obtain_edge( roadnet, road2, data_flag=True )
roadlen2 = data2.get( length_attr, np.inf )
res = []
x = GLOBAL.x ; y = GLOBAL.y
canvas = [
-x, # x >= 0
x - roadlen1, # x <= roadlen1
-y, # y >= 0
y - roadlen2 # y <= roadlen2
]
""" there are three "interesting" cases """
if road1 == road2 :
# case 1: road1 == road2, y >= x
options = _options_roads_eq_ygeqx( roadnet, road1, length_attr )
zones = _zonify_options( options )
for zone in zones :
zone.extend( canvas )
zone.append( x - y )
phases = zip( options, zones )
res.extend( phases )
# case 2: road1 == road2, y <= x
options = _options_roads_eq_yleqx( roadnet, road1, length_attr )
zones = _zonify_options( options )
for zone in zones :
zone.extend( canvas )
zone.append( y - x )
phases = zip( options, zones )
res.extend( phases )
else :
# case 3: road1 != road2
options = _options_roads_neq( roadnet, road1, road2, length_attr )
zones = _zonify_options( options )
for zone in zones :
zone.extend( canvas )
phases = zip( options, zones )
res.extend( phases )
return res
def computeImbalance( roadmap, rategraph, rate_attr='rate', **kwargs ) :
weight1_attr = kwargs.get( 'weight1_attr', 'weight1' )
weight2_attr = kwargs.get( 'weight2_attr', 'weight2' )
for road in rategraph.nodes_iter() :
supply = rategraph.in_degree( road, rate_attr ) - rategraph.out_degree( road, rate_attr )
_, road_data = ROAD.obtain_edge( roadmap, road, True )
if supply > 0. :
road_data[weight1_attr] = supply
elif supply < 0. :
road_data[weight2_attr] = -supply
def _options_roads_eq_yleqx( roadnet, road, length_attr ) :
edge, data = ROAD.obtain_edge( roadnet, road, data_flag=True )
u,v,_ = edge ; roadlen = data.get( length_attr, np.inf )
p = ROAD.roadify( roadnet, u, length_attr )
q = ROAD.roadify( roadnet, v, length_attr )
x = GLOBAL.x ; y = GLOBAL.y
sojourn_cost = roadlen - x + ROAD.distance( roadnet, q, p, length_attr ) + y # a path using the rest of the network
options = [ sojourn_cost ]
if not data.get( 'oneway', False ) :
options.append( x - y )
return options
def samplepair( roadnet, distr1, distr2=None, length_attr='length' ) :
""" assume distr sums to one; if not, no guaranteed behavior """
if distr2 is not None : raise 'not implemented yet'
# choose appropriately, randomly... can probably do better
x = np.random.rand()
X = 0.
for (road1,road2), prob in distr1.iteritems() :
X += prob
if X >= x : break
_, data1 = ROAD.obtain_edge( roadnet, road1, data_flag=True )
_, data2 = ROAD.obtain_edge( roadnet, road2, data_flag=True )
roadlen1 = data1.get( 'length' )
roadlen2 = data2.get( 'length' )
x = roadlen1 * np.random.rand()
y = roadlen2 * np.random.rand()
p = ROAD.RoadAddress( road1, x )
q = ROAD.RoadAddress( road2, y )
return p, q
def position(address, roadmap, pos, length_attr='length'):
"""
get the Euclidean position of a street address,
given roadmap and dictionary of vertex positions
"""
road, coord = address
coord = float(coord)
u, v, key = ROAD.obtain_edge(roadmap, road)
assert key == road
data = ROAD.get_road_data(road, roadmap)
width = data.get( length_attr, 1 )
#ROAD.get_edge_data( )
x = pos[u]
vec = pos[v] - x
return x + vec * coord / width
