graph_empty() creates an empty graph with a specified number of vertices.
An empty graph in igraph is a graph with no edges, which may have vertices.
graph_copy() creates a deep copy of the graph.
Normal assignment like g2 = g1 creates a shallow copy, which means that
the internal data is shared between the two R objects, and the modification
on one of them will affect the other.
Arguments
- n
An integer, the number of vertices in the graph.
- directed
A logical value, whether to consider directed paths. Ignored for undirected graphs.
- graph
An
igraph_ptrobject.
Value
An igraph_ptr object.
See also
Other deterministic generators:
graph_create(),
graph_famous(),
graph_full(),
graph_kary_tree(),
graph_square_lattice(),
graph_star()
Examples
g = graph_empty(4L)
g
#> $V tibble [4 × 0] (S3: tbl_df/tbl/data.frame)
#> Named list()
#> # A tibble: 0 × 2
#> # ℹ 2 variables: from <int>, to <int>
g_shallow = g
g_deep = graph_copy(g)
add_edges(g, seq_len(4L))
g_shallow
#> $V tibble [4 × 0] (S3: tbl_df/tbl/data.frame)
#> Named list()
#> # A tibble: 2 × 2
#> from to
#> <int> <int>
#> 1 1 2
#> 2 3 4
g_deep
#> $V tibble [4 × 0] (S3: tbl_df/tbl/data.frame)
#> Named list()
#> # A tibble: 0 × 2
#> # ℹ 2 variables: from <int>, to <int>