Transforms a DAG into an essential graph.
The graph matrix as produced from
This can be either NULL or 1 or 2. type = 1 means that the matrix contains 0, 1, 2, 3 where G[i, j] = g[j, i] = 0, means there is no edge between nodes i and j, G[i, j] = g[j, i] = 1, there is an edge between nodes i and j and G[i, j] = 2 and G[j, i] = 3 means that there is an arrow from node i to node j. If type 2, the matrix contains 0 for no edge and 1 for a directed edge. In this case, G[i,j]=1 and G[j,i]=0 means that there is an arrow from node i to node j. If you are not sure of what you have, just leave it NULL, the function will check to which case your matrix belongs.
The function is an R translation from an old matlab code.
The matrix of the essential graph.
Ioannis Tsamardinos and Michail Tsagris
R implementation and documentation: Giorgos Athineou <firstname.lastname@example.org>, Ioannis Tsamardinos <email@example.com> and and Michail Tsagris <firstname.lastname@example.org>
Chickering, D.M. (1995). A transformational characterization of equivalent Bayesian network structures. Proceedings of the 11th Conference on Uncertainty in Artificial Intelligence, Montreal, Canada, 87-98.
plotnetwork, nei, pc.or
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