RNeo4j (version 1.6.4)

shortestPath: Shortest Paths and Weighted Shortest Paths

Description

Retrieve the shortest path between two nodes.

Usage

shortestPath(fromNode, relType, toNode, direction = "out", max_depth = 1, cost_property = character())

Arguments

fromNode

A node object.

relType

A character string. The relationship type to traverse.

toNode

A node object.

direction

A character string. The relationship direction to traverse; this can be either "in", "out", or "all".

max_depth

An integer. The maximum depth of the path.

cost_property

A character string. If retrieving a weighted shortest path, the name of the relationship property that contains the weights.

Value

A path object.

See Also

allShortestPaths

Examples

## Not run: 
# graph = startGraph("http://localhost:7474/db/data/")
# clear(graph)
# 
# alice = createNode(graph, "Person", name = "Alice")
# bob = createNode(graph, "Person", name = "Bob")
# charles = createNode(graph, "Person", name = "Charles")
# david = createNode(graph, "Person", name = "David")
# elaine = createNode(graph, "Person", name = "Elaine")
# 
# r1 = createRel(alice, "KNOWS", bob, weight=1.5)
# r2 = createRel(bob, "KNOWS", charles, weight=2)
# r3 = createRel(bob, "KNOWS", david, weight=4)
# r4 = createRel(charles, "KNOWS", david, weight=1)
# r5 = createRel(alice, "KNOWS", elaine, weight=2)
# r6 = createRel(elaine, "KNOWS", david, weight=2.5)
# 
# # The default max_depth of 1 will not find a path.
# # There are no length-1 paths between alice and david.
# p = shortestPath(alice, "KNOWS", david)
# is.null(p)
# 
# # Set the max_depth to 4.
# p = shortestPath(alice, "KNOWS", david, max_depth = 4)
# p$length
# n = nodes(p)
# sapply(n, function(x) x$name)
# 
# # Setting the direction to "in" and traversing from alice to david will not find a path.
# p = shortestPath(alice, "KNOWS", david, direction = "in", max_depth = 4)
# is.null(p)
# 
# # Setting the direction to "in" and traversing from david to alice will find a path.
# p = shortestPath(david, "KNOWS", alice, direction = "in", max_depth = 4)
# p$length
# n = nodes(p)
# sapply(n, function(x) x$name)
# 
# # Find the weighted shortest path between Alice and David.
# p = shortestPath(alice, "KNOWS", david, cost_property="weight")
# p$length
# p$weight
# nodes(p)
# ## End(Not run)