phylobase (version 0.8.2)

getNode: Node and Edge look-up functions

Description

Functions for retrieving node and edge IDs (possibly with corresponding labels) from a phylogenetic tree.

Usage

getNode(x, node, type = c("all", "tip", "internal"), missing = c("warn", "OK", "fail"))
"getNode"(x, node, type = c("all", "tip", "internal"), missing = c("warn", "OK", "fail"))
getEdge(x, node, type = c("descendant", "ancestor"), missing = c("warn", "OK", "fail"))
"getEdge"(x, node, type = c("descendant", "ancestor"), missing = c("warn", "OK", "fail"))

Arguments

x
a phylo4 object (or one inheriting from phylo4, e.g. a phylo4d object)
node
either an integer vector corresponding to node ID numbers, or a character vector corresponding to node labels; if missing, all nodes appropriate to the specified type will be returned by getNode, and all edges appropriate to the specified type will be returned by getEdge.
type
(getNode) specify whether to return nodes matching "all" tree nodes (default), only "tip" nodes, or only "internal" nodes; (nodeId, edgeId) specify whether to return "all" tree nodes, or only those corresponding to "tip", "internal", or "root" nodes; (getEdge) specify whether to look up edges based on their descendant node ("descendant") or ancestral node ("ancestor")
missing
what to do if some requested node IDs or names are not in the tree: warn, do nothing, or stop with an error

Value

list("getNode")
returns a named integer vector of node IDs, in the order of input nodes if provided, otherwise in nodeId order
list("getEdge")
returns a named character vector of edge IDs, in the order of input nodes if provide, otherwise in nodeId order
list("nodeId")
returns an unnamed integer vector of node IDs, in ascending order
list("getEdge")
returns an unnamed character vector of edge IDs, in edge matrix order

Details

getNode and getEdge are primarily intended for looking up the IDs either of nodes themselves or of edges associated with those nodes. Note that they behave quite differently. With getNode, any input nodes are looked up against tree nodes of the specified type, and those that match are returned as numeric node IDs with node labels (if they exist) as element names. With getEdge, any input nodes are looked up against edge ends of the specified type, and those that match are returned as character edge IDs with the corresponding node ID as element names.

If missing is “warn” or “OK”, NA is returned for any nodes that are unmatched for the specified type. This can provide a mechanism for filtering a set of nodes or edges.

nodeId provides similar output to getNode in the case when no node is supplied, but it is faster and returns an unnamed vector of the numeric IDs of all nodes of the specified node type. Similarly, edgeId simply returns an unnamed vector of the character IDs of all edges for which the descendant node is of the specified node type.

Examples

Run this code

  data(geospiza)
  nodeLabels(geospiza) <- LETTERS[1:nNodes(geospiza)]
  plot(as(geospiza, "phylo4"), show.node.label=TRUE)
  getNode(geospiza, 18)
  getNode(geospiza, "D")
  getEdge(geospiza, "D")
  getEdge(geospiza, "D", type="ancestor")

  ## match nodes only to tip nodes, flagging invalid cases as NA
  getNode(geospiza, c(1, 18, 999), type="tip", missing="OK")

  ## get all edges that descend from internal nodes
  getEdge(geospiza, type="ancestor")

  ## identify an edge from its terminal node
  getEdge(geospiza, c("olivacea", "B", "fortis"))
  getNode(geospiza, c("olivacea", "B", "fortis"))
  edges(geospiza)[c(26, 1, 11),]

  ## quickly get all tip node IDs and tip edge IDs
  nodeId(geospiza, "tip")
  edgeId(geospiza, "tip")

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