Define polycenter(verts)= Prgm :Local k,numverts,points,xg,yg,x,y,xc,yc,s,st :numverts:=((dim(verts))/(2)) :points:=exact(augment(verts,{verts[1],verts[2]})) :For k,1,((dim(points))/(2)) :x[k]:=points[2*k-1] :y[k]:=points[2*k] :EndFor :xc:=((seqn(x[n]+x[n+1],numverts))/(3)) :yc:=((seqn(y[n]+y[n+1],numverts))/(3)) :s:=((seqn(x[n+1]*y[n]-y[n+1]*x[n],numverts))/(2)) :st:=sum(s) :xg:=((sum(s*xc))/(st)) :yg:=((sum(s*yc))/(st)) :Disp "numVerts: ",numverts :Disp "center x: ",xc :Disp "center y: ",yc :Disp "each area: ",s :Disp "total area: ",st :Disp "xg, yg: ",{xg,yg} :EndPrgm