search for: octahedron

Hi, I would like to get from a plot the size of the symbols plotted. Imagine I have the following plot function : plot(1:2,1:2, pch=15, cex=4) I would like the get the values SIZE1 and SIZE2 so that if I plot the following rectangle : rect(1.5,1.5, 1.5+SIZE1, 1.5+SIZE2) then the size of this square is exactely the same as the one of the symbols that have been plotted. Thanks for any idea. --

...up with something better than PVQ. What I wound up writing is something I call an "octagon quantizer. In two dimensions, PVQ uses a "diamond" (square) shape. An octagon code (OVQ) uses an octagon, which is a much better approximation to the circle. In two dimensions, PVQ uses an octahedron, and OVQ uses a rhombicuboctahedron, which is (again) a much better approximation to the sphere. In OVQ, the resolution parameter K is replaced by two (int) parameters A and B. Quantization then proceeds very simply: all components greater than B are subjected to PVQ (after subtracting B) with re...