Dear all, there is a bug in computing the REGULAR property of a polyhedral fan. If I create the following fan, I get a negative result for REGULAR, however it is the normal fan of a polytope. Best, Sebastian fan > $rays=[[1,0,0,0],[0,1,0,0],[0,0,1,0],[1,0,-1,-1],[-1,-1,0,0]]; fan > $cones=[[1,2,3,5]...