function [supernodes,edges] = hole(center,rad,degrees,inc);
%
%  function [supernodes,edges] = hole(center,rad,degrees);
%
%  Input:
%     center = x & y coordinates of hole center
%     rad = radius of hold
%     degrees = number of degrees between supernodes (default 30)
%     inc = increment to add to supernode numbers (default 0)
%  Output:
%     supernodes = list of points on the hole circumference
%     edges = list of edges defining the hole
%
error(nargchk(2,4,nargin));
if nargin==2
    degrees = 30;
end
if nargin < 4
    inc = 0;
end
theta = (0:degrees:(360-degrees))*pi/180;
theta = theta(:);
xc = center(1);
yc = center(2);
supernodes = [xc+rad*cos(theta) yc+rad*sin(theta)];
ns = length(supernodes);
edges = [1:ns ; [2:ns 1]]';
edges(end,2) = 1;
edges = edges + inc;