PolyhedralGeometry: simplified operations with PolyhedralFan

Author: YueRen

Diff for: src/PolyhedralGeometry/PolyhedralFan/standard_constructions.jl

@@ -411,35 +411,26 @@ end
 ## Scalar multiplication
 ###############################################################################
 
-function multiply_by_nonzero_scalar(u::PointVector{QQFieldElem}, c::QQFieldElem)
-  return u .* c
-end
-function multiply_by_nonzero_scalar(u::RayVector{QQFieldElem}, c::QQFieldElem)
-  return (c<0 ? -u : u)
-end
-
-function *(c::QQFieldElem, Sigma::PolyhedralFan)
-  # if scalar is zero, return polyhedral complex consisting only of the origin
+function *(c::scalar_types_extended, Sigma::PolyhedralFan)
+  # if scalar is zero, return polyhedral fan consisting only of the origin
   if iszero(c)
-    return polyhedral_complex(convex_hull(zero_matrix(QQ,1,ambient_dim(Sigma))))
+    return polyhedral_fan(positive_hull(zero_matrix(coefficient_field(Sigma),1,ambient_dim(Sigma))))
   end
 
-  # if scalar is non-zero, multiple all vertices and rays by said scalar
+  # if scalar is non-zero, multiple all rays by said scalar
   SigmaRays = first(rays_modulo_lineality(Sigma))
   SigmaLineality = lineality_space(Sigma)
   SigmaIncidence = maximal_cones(IncidenceMatrix,Sigma)
-  return polyhedral_fan(SigmaIncidence, multiply_by_nonzero_scalar.(SigmaRays,c), SigmaLineality)
+  return polyhedral_fan(coefficient_field(Sigma), SigmaIncidence, SigmaRays .* c, SigmaLineality)
 end
-*(c::RationalUnion, Sigma::PolyhedralFan) = QQ(c)*Sigma
-*(Sigma::PolyhedralFan,c::RationalUnion) = c*Sigma
+*(Sigma::PolyhedralFan,c::scalar_types_extended) = c*Sigma
 
 ###############################################################################
 ## Negation
 ###############################################################################
 
 function -(Sigma::PolyhedralFan)
-  SigmaRays = first(rays_modulo_lineality(Sigma))
-  SigmaLineality = lineality_space(Sigma)
+  SigmaRays, SigmaLineality = first(rays_modulo_lineality(Sigma))
   SigmaIncidence = maximal_cones(IncidenceMatrix,Sigma)
-  return polyhedral_fan(SigmaIncidence, -SigmaRays, SigmaLineality)
+  return polyhedral_fan(coefficient_field(Sigma), SigmaIncidence, -SigmaRays, SigmaLineality)
 end