Documentation
¶
Overview ¶
Package route finds the shortest route between two points along a geometrical network (e.g., a road network). For now, all network links are assumed to be bi-directional (e.g., all roads are two-way).
Example ¶
link1 := geom.LineString{
geom.Point{X: 0, Y: 0},
geom.Point{X: 0, Y: 1},
geom.Point{X: 1, Y: 1},
geom.Point{X: 8, Y: 1},
geom.Point{X: 8, Y: 4},
} // Distance = 12
link2 := geom.LineString{
geom.Point{X: 8, Y: 4}, // link2 beginning == link1 end
geom.Point{X: 8, Y: -6},
} // Distance = 10
startingPoint := geom.Point{X: 0, Y: -1}
endingPoint := geom.Point{X: 6, Y: -6}
net := NewNetwork(Time)
net.AddLink(link1, 6)
net.AddLink(link2, 2)
route, distance, time, startDistance, endDistance :=
net.ShortestRoute(startingPoint, endingPoint)
fmt.Println(route, distance, time, startDistance, endDistance)
Output: [[{0 0} {0 1} {1 1} {8 1} {8 4}] [{8 4} {8 -6}]] 22 7 1 2
Index ¶
- type MinimizeOption
- type Network
- func (net *Network) AddLink(l geom.LineString, speed float64)
- func (net Network) Edge(u, v int64) graph.Edge
- func (net Network) From(n int64) graph.Nodes
- func (net Network) Has(n int64) bool
- func (net Network) HasEdge(x, y int64) bool
- func (net Network) HasEdgeBetween(xid, yid int64) bool
- func (net Network) Node(id int64) graph.Node
- func (net Network) Nodes() graph.Nodes
- func (net Network) ShortestRoute(from, to geom.Point) (route geom.MultiLineString, distance, time, startDistance, endDistance float64)
- func (net *Network) Weight(e graph.Edge) float64
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type MinimizeOption ¶
type MinimizeOption float64
MinimizeOption specifies how the shortest route should be chosen.
const ( // Distance specifies that we are looking to travel the minimum distance. Distance MinimizeOption = iota // Time specifies that we are looking to travel the minimum time. Time )
type Network ¶
type Network struct {
// contains filtered or unexported fields
}
A Network is a holder for network data (e.g., a road network)
func NewNetwork ¶
func NewNetwork(m MinimizeOption) *Network
NewNetwork initializes a new Network where m determines how to choose the shortest route (either by Distance or Time).
func (*Network) AddLink ¶
func (net *Network) AddLink(l geom.LineString, speed float64)
AddLink adds a new link l (which is a line string) to the Network, where speed is the speed traveled along the link and should have units that are compatible with the units of l (for instance, if l is in units of meters, and speed is in units of m/s, the time results will be in units of seconds).
func (Network) Edge ¶
Edge returns the edge from u to v if such an edge exists and nil otherwise. The node v must be directly reachable from u as defined by the From method. It is not intended for direct use in this package.
func (Network) From ¶
From returns all nodes that can be reached directly from the given node. It is not intended for direct use in this package.
func (Network) Has ¶
Has returns whether the node exists within the graph. It is not intended for direct use in this package.
func (Network) HasEdge ¶
HasEdge returns whether an edge exists between nodes x and y without considering direction. It is not intended for direct use in this package.
func (Network) HasEdgeBetween ¶
HasEdgeBetween returns whether an edge exists between nodes x and y without considering direction.
func (Network) Nodes ¶
Nodes returns all the nodes in the graph. It is not intended for direct use in this package.
func (Network) ShortestRoute ¶
func (net Network) ShortestRoute(from, to geom.Point) ( route geom.MultiLineString, distance, time, startDistance, endDistance float64)
ShortestRoute calculates the shortest route along the network between the from and to points. It returns the route ("path"), the distance traveled along the route ("distance"), the time it would take travel along the route ("time"; this does not count time spent getting to and from the network), the distance traveled from the starting point to get to the nearest node (e.g., intersection) along the route ("startDistance") and the distance traveled to the ending point from the nearest node along the route ("endDistance"). This function does not change the Network, so multiple function calls can be run concurrently.
Source Files