These functions return logical vectors the length of the nodes in a network identifying which hold certain properties.

node_is_cutpoint() and node_is_isolate() are useful for identifying nodes that are in particular positions in the network. More can be added here.

node_is_max() and node_is_min() are more generally useful for converting the results from some node measure into a mark-class object. They can be particularly useful for highlighting which node or nodes are key because they minimise or, more often, maximise some measure.

node_is_cutpoint(object)

node_is_isolate(object)

node_is_core(object)

node_is_random(object, size = 1)

node_is_max(node_measure, ranks = 1)

node_is_min(node_measure, ranks = 1)

Arguments

object

An object of a migraph-consistent class:

  • matrix (adjacency or incidence) from {base} R

  • edgelist, a data frame from {base} R or tibble from {tibble}

  • igraph, from the {igraph} package

  • network, from the {network} package

  • tbl_graph, from the {tidygraph} package

size

The number of nodes to select (as TRUE).

node_measure

An object created by a node_ measure.

ranks

The number of ranks of max or min to return. For example, ranks = 3 will return TRUE for nodes with scores equal to any of the top (or, for node_is_min(), bottom) three scores. By default, ranks = 1.

Functions

  • node_is_cutpoint(): Returns logical of which nodes cut or act as articulation points in a network, increasing the number of connected components in a graph when removed.

  • node_is_isolate(): Returns logical of which nodes are isolates, with neither incoming nor outgoing ties.

  • node_is_core(): Returns logical of which nodes are members of the core of the network.

  • node_is_random(): Returns a logical vector indicating a random selection of nodes as TRUE.

  • node_is_max(): Returns logical of which nodes hold the maximum of some measure

  • node_is_min(): Returns logical of which nodes hold the minimum of some measure

See also

Other marks: is(), mark_ties

Examples

node_is_cutpoint(ison_brandes)
#>   V1    V2    V3    V4    V5    V6    V7    V8    V9    V10   V11  
#> 1 FALSE FALSE TRUE  TRUE  FALSE FALSE FALSE FALSE TRUE  FALSE FALSE
node_is_isolate(ison_brandes)
#>   V1    V2    V3    V4    V5    V6    V7    V8    V9    V10   V11  
#> 1 FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
node_is_core(ison_brandes)
#>   V1    V2    V3    V4    V5    V6    V7    V8    V9    V10   V11  
#> 1 FALSE FALSE TRUE  TRUE  FALSE FALSE FALSE FALSE TRUE  FALSE FALSE
node_is_random(ison_brandes, 2)
#>   V1    V2    V3    V4    V5    V6    V7    V8    V9    V10   V11  
#> 1 FALSE FALSE FALSE FALSE TRUE  TRUE  FALSE FALSE FALSE FALSE FALSE
node_is_max(node_degree(ison_brandes))
#>   V1    V2    V3    V4    V5    V6    V7    V8    V9    V10   V11  
#> 1 FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE  FALSE FALSE
node_is_min(node_degree(ison_brandes))
#>   V1    V2    V3    V4    V5    V6    V7    V8    V9    V10   V11  
#> 1 TRUE  TRUE  FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE  TRUE