```
## 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 any paths.
# # There are no length-1 paths between alice and david.
# p = allShortestPaths(alice, "KNOWS", david)
# is.null(p)
#
# # Set the max_depth to 4.
# p = allShortestPaths(alice, "KNOWS", david, max_depth = 4)
# n = lapply(p, nodes)
# lapply(n, function(x) sapply(x, function(y) y$name))
#
# # Setting the direction to "in" and traversing from alice to david will not find a path.
# p = allShortestPaths(alice, "KNOWS", david, direction = "in", max_depth = 4)
# is.null(p)
#
# # Setting the direction to "in" and traversing from david to alice will find paths.
# p = allShortestPaths(david, "KNOWS", alice, direction = "in", max_depth = 4)
# n = lapply(p, nodes)
# lapply(n, function(x) sapply(x, function(y) y$name))
#
# # Find all the weighted shortest paths between Alice and David.
# p = allShortestPaths(alice, "KNOWS", david, cost_property="weight")
#
# p[[1]]$length
# p[[1]]$weight
# nodes(p[[1]])
#
# p[[2]]$length
# p[[2]]$weight
# nodes(p[[2]])
# ## End(Not run)
```

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