ETREE

 

 Elimination tree of a matrix.

  p = etree(A) returns an elimination tree for the square

  symmetric matrix whose upper triangle is that of A.

  p(j) is the parent of column j in the tree, 

  or 0 if j is a root.

 

 

  p = etree(A,'col') returns the elimination tree of A'*A.

  p = etree(A,'sym') is the same as p = etree(A).

 

 

  [p,q] = etree(...) also returns a postorder permutation q on the tree.

 

 

  See also TREELAYOUT3HP6LU, TREEPLOT8LAUZ1, ETREEPLOT1JG242R.