Determine which XY points were meged by DelaunayTri to match up Zs

Consider: 3 identical sized arrays X,Y,Z with some dup X,Y points.

DT = DelaunayTri(X,Y); Gives a warning, but then:

F = TriScatteredInterp(DT,Z) (or anything elsen matchin Z to the nodes in DT)

FAILS

What is the least inefficient way to reample the Zs to match?

I'd recommend adding an output (IND) to DelaunayTri so that ZC = accumarray(IND,Z) matches DT.