Merge pull request #2492 from oscar-system/lk/vector_tropical_number

Project.toml

@@ -31,7 +31,7 @@ GAP = "0.9.4"
 Hecke = "0.18.13"
 JSON = "^0.20, ^0.21"
 Nemo = "0.34.3"
-Polymake = "0.9.0"
+Polymake = "0.10.0"
 Preferences = "1"
 RandomExtensions = "0.4.3"
 RecipesBase = "1.2.1"

src/PolyhedralGeometry/LP_file_format.jl

@@ -96,7 +96,7 @@ julia> save_mps(stdout, milp)
 * Columns:	2
 * Format:	MPS
 *
-Name          unnamed#0
+NAME          unnamed#0
 ROWS
  N  C0000000
  G  R0000000

src/TropicalGeometry/TropicalGeometry.jl

@@ -7,46 +7,35 @@ include("groebner_basis.jl")
 include("groebner_polyhedron.jl")
 include("points.jl")
 
-# Temporarily we will turn tropical polynomials into strings. This will be
-# removed once Polymake.jl wraps its tropical polynomials and tropical numbers
-#
-# Warning: This function ignores all boundary cases!
-function tropical_polynomial_to_polymake(f)
-    fstr = ""
-    if convention(base_ring(f)) == min
-        fstr *= "min("
-    else
-        fstr *= "max("
-    end
-    td = total_degree(f)
-    for i in 1:length(f)
-        fstr *= repr(coeff(f,i).data)
-        e = exponent_vector(f,i)
-        if td - sum(e) != 0
-            fstr *= "+"
-            fstr *= repr(td-sum(e))
-            fstr *= "x_0"
-        end
-        if !iszero(e)
-            for j in 1:length(e)
-                if !iszero(e[j])
-                    fstr *= "+"
-                    fstr *= repr(e[j])
-                    fstr *= "*x_"
-                    fstr *= repr(j)
-                end
-            end
-        end
-        if i != length(f)
-            fstr *= ","
-        end
-    end
-    fstr *= ")"
-    result = ["x_"*repr(i) for i in 0:nvars(parent(f))]
-    prepend!(result, [fstr])
-    return result
+# Decompose a tropical polynomial into parts that Polymake can eat.
+# First function deals with the coefficients,
+# Second function then deals with the entire polynomial.
+function homogenize_and_convert_to_pm(t::Oscar.TropicalSemiringElem{S}) where S<:Union{typeof(max), typeof(min)}
+   Add = S == typeof(max) ? Polymake.Max : Polymake.Min
+   if isinf(t)
+      return Polymake.TropicalNumber{Add}()
+   else
+      return Polymake.TropicalNumber{Add}(Polymake.new_rational_from_fmpq(data(t)))
+   end
 end
 
+function homogenize_and_convert_to_pm(f::Oscar.MPolyRingElem{Oscar.TropicalSemiringElem{S}}) where S<:Union{typeof(max), typeof(min)}
+   Add = S == typeof(max) ? Polymake.Max : Polymake.Min
+   coeffs = (Polymake.TropicalNumber{Add})[]
+   td = total_degree(f)
+   exps = (Vector{Int})[]
+   for term in terms(f)
+      push!(coeffs, homogenize_and_convert_to_pm(leading_coefficient(term)))
+      exp = leading_exponent_vector(term)
+      prepend!(exp, td-sum(exp))
+      push!(exps, exp)
+   end
+   exps = matrix(ZZ, exps)
+   coeffs = Polymake.Vector{Polymake.TropicalNumber{Add, Polymake.Rational}}(coeffs)
+   return coeffs, exps
+end
+
+
 
 ###
 # Allow gcd of vectors of univariate rational polynomials

src/TropicalGeometry/hypersurface.jl

@@ -78,9 +78,8 @@ function TropicalHypersurface(f::AbstractAlgebra.Generic.MPoly{Oscar.TropicalSem
         error("Tropical hypersurfaces of constant polynomials not supported.")
     end
     M = convention(base_ring(f))
-    fstr = Tuple(tropical_polynomial_to_polymake(f))
-    pmpoly = Polymake.common.totropicalpolynomial(fstr...)
-    pmhypproj = Polymake.tropical.Hypersurface{M}(POLYNOMIAL=pmpoly)
+    coeffs, exps = homogenize_and_convert_to_pm(f)
+    pmhypproj = Polymake.tropical.Hypersurface{M}(MONOMIALS=exps, COEFFICIENTS=coeffs)
     pmhyp = Polymake.tropical.affine_chart(pmhypproj)
     Vf = TropicalHypersurface{M, true}(polyhedral_complex(pmhyp))
     w = pmhypproj.WEIGHTS

test/PolyhedralGeometry/linear_program.jl

@@ -85,7 +85,7 @@
                   * Columns:	2
                   * Format:	MPS
                   *
-                  Name          unnamed#2
+                  NAME          unnamed#2
                   ROWS
                    N  C0000000
                    G  R0000000

test/TropicalGeometry/hypersurface.jl

@@ -0,0 +1,14 @@
+@testset "hypersurface" begin
+  for addition in (max, min)
+    T = TropicalSemiring(addition)
+    R,(x,y,z) = PolynomialRing(T,3)
+    b = [T(10),T(3//2095), T(-5//2)]
+    m = [[1,0,1],[0,3,4],[1,0,7]]
+    f = R(b,m)
+    hyp = TropicalHypersurface(f)
+    coeffs, exps = Oscar.homogenize_and_convert_to_pm(f)
+    @test hyp isa TropicalHypersurface{addition}
+    @test coeffs == get_attribute(hyp, :polymake_bigobject).COEFFICIENTS
+    @test exps == matrix(ZZ, get_attribute(hyp, :polymake_bigobject).MONOMIALS)
+  end
+end

test/TropicalGeometry/runtests.jl

@@ -3,3 +3,4 @@ using Oscar
 include("groebner_basis.jl")
 include("groebner_fan.jl")
 include("initial.jl")
+include("hypersurface.jl")