scale(alpha, beta)

   function S = scale(alpha, beta)

%SCALE    scaling matrix.
%         SCALE(ALPHA, BETA) x scaled by alpha, y scaled by beta.
%         The scaling of an object is performed by multiplying
%         SCALE by the 3 by n matrix defining the object,
%         for example: scale(alpha, beta)*object

S = [ alpha 0 0 ; 0 beta 0; 0 0 1 ];