function setup_rotate
% This function sets up the current figure for 3d rotation.
% press a mouse button while over the figure window to start the 
% rotation, press again to stop.  moving the mouse up and down 
% controls the altitude; left and right control the azimuth (rotation
% about the z axis.
 
%Eric Soroos
%10-21-95

set(gcf,'windowbuttondownfcn','alternate_az(gcf);');