Conveniently adds a node to an existing DAG, inserting its coordinates and
label before the outcome node. Also updates the arcs correspondingly.
Usage
add.node(dag, name = "unknown", type = 1, x = NA, y = NA)
Arguments
dag
The DAG to which the node is to be added.
name
Label for the node (defaults to "unknown").
type
Type of node (1=covariable, 2=unknown); defaults to 1.
x
X coordinate for the node position.
y
Y coordinate for the node position.
Value
A DAG with the new node added.
Details
If no x and y coordinates are provided, the function places the node
in an arbitrary position, slightly different with each additional
node, so that one can more easily replace the nodes afterwards
using dag.move.