Hello, I'm new at polymake and I found something strange. I wrote application "fan"; $f = new PolyhedralFan(RAYS=>[[-1,0,0],[0,-1,0],[1,1,0]],MAXIMAL_CONES=>[[0],[1],[2]]); and then $f->VISUAL(PointColor=> 'blue', PointBorderColor=> 'blue', VertexBorderColor=> 'blue', VertexColor=>'blue', ...