Usage
graph_center(graph, ..., weights = NULL, mode = c("all", "out", "in", "total"))
Arguments
- graph
The input graph, it can be directed or undirected.
- ...
These dots are for future extensions and must be empty.
- weights
Possibly a numeric vector giving edge weights. If this is
NULL
and the graph has aweight
edge attribute, then the attribute is used. If this isNA
then no weights are used (even if the graph has aweight
attribute). In a weighted graph, the length of a path is the sum of the weights of its constituent edges.- mode
Character constant, gives whether the shortest paths to or from the given vertices should be calculated for directed graphs. If
out
then the shortest paths from the vertex, ifin
then to it will be considered. Ifall
, the default, then the graph is treated as undirected, i.e. edge directions are not taken into account. This argument is ignored for undirected graphs.
See also
Other paths:
all_simple_paths()
,
diameter()
,
distance_table()
,
eccentricity()
,
radius()
Examples
tree <- make_tree(100, 7)
graph_center(tree)
#> + 2/100 vertices, from 14daec4:
#> [1] 1 2
graph_center(tree, mode = "in")
#> + 1/100 vertex, from 14daec4:
#> [1] 1
graph_center(tree, mode = "out")
#> + 85/100 vertices, from 14daec4:
#> [1] 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
#> [20] 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53
#> [39] 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72
#> [58] 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91
#> [77] 92 93 94 95 96 97 98 99 100
# Without and with weights
ring <- make_ring(10)
graph_center(ring)
#> + 10/10 vertices, from f0d30cd:
#> [1] 1 2 3 4 5 6 7 8 9 10
# Add weights
E(ring)$weight <- seq_len(ecount(ring))
graph_center(ring)
#> + 1/10 vertex, from f0d30cd:
#> [1] 7