Merge pull request #203 from hannes14/lift_rest

changed lift: also return a rest
oscar-system · Mar 6, 2020 · c23b7f3 · c23b7f3
2 parents 9f85c21 + b513827
commit c23b7f3
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Showing 3 changed files with 28 additions and 23 deletions.
diff --git a/deps/src/ideals.cpp b/deps/src/ideals.cpp
@@ -187,10 +187,12 @@ void singular_define_ideals(jlcxx::Module & Singular)
     Singular.method("id_Lift", [](ideal m, ideal sm, ring o) {
         const ring origin = currRing;
         rChangeCurrRing(o);
-        ideal res = idLift(m, sm, NULL, FALSE, FALSE);
-	res->rank = IDELEMS(m);
+        ideal rest;
+        ideal res = idLift(m, sm, &rest, FALSE, FALSE);
+        rest->rank = m->rank;
+        res->rank = IDELEMS(m);
         rChangeCurrRing(origin);
-        return res;
+        return std::make_tuple(res, rest);
     });
 
     Singular.method("id_Modulo", [](ideal a, ideal b, ring o) {
@@ -228,14 +230,14 @@ void singular_define_ideals(jlcxx::Module & Singular)
     Singular.method("id_vdim", [](ideal I, ring r) {
         const ring origin = currRing;
         rChangeCurrRing(r);
-	int n=scMult0Int(I, r->qideal);
-	rChangeCurrRing(origin);
-	return n;
+        int n=scMult0Int(I, r->qideal);
+        rChangeCurrRing(origin);
+        return n;
     });
 
     Singular.method("id_kbase", [](ideal I, ring r) {
         ideal res;
-	const ring origin = currRing;
+        const ring origin = currRing;
         rChangeCurrRing(r);
         res = scKBase(-1, I, r->qideal);
         rChangeCurrRing(origin);
@@ -255,19 +257,19 @@ void singular_define_ideals(jlcxx::Module & Singular)
         const ring origin = currRing;
         rChangeCurrRing(pr);
         ideal I = maMapIdeal(map_id, pr, im_id, im, reinterpret_cast<nMapFunc>(cf_map));
-	rChangeCurrRing(origin);
-	return I;
+        rChangeCurrRing(origin);
+        return I;
     });
     Singular.method("idMinBase", [](ideal I, ring r) {
         const ring origin = currRing;
         rChangeCurrRing(r);
         ideal J = idMinBase(I);
-	rChangeCurrRing(origin);
-	return J;
+        rChangeCurrRing(origin);
+        return J;
     });
     Singular.method("scIndIndset", [](ideal I, ring r, jlcxx::ArrayRef<int> a, bool all) {
         const ring origin = currRing;
-	rChangeCurrRing(r);
+        rChangeCurrRing(r);
         lists L = scIndIndset(I, all, r->qideal);
         int n = rVar(r);
         int m = lSize(L);
@@ -292,21 +294,21 @@ void singular_define_ideals(jlcxx::Module & Singular)
               a.push_back(content[j]);
            }
         }
-	rChangeCurrRing(origin);
+        rChangeCurrRing(origin);
     });
     Singular.method("scDimInt", [](ideal I, ring R) {
         const ring origin = currRing;
-	rChangeCurrRing(R);
+        rChangeCurrRing(R);
         int k = scDimInt(I, R->qideal);
-	rChangeCurrRing(origin);
-	return k;
+        rChangeCurrRing(origin);
+        return k;
     });
     Singular.method("fglmzero", [](ideal Isrc, ring Rsrc, ring Rdest ) {
         const ring origin = currRing;
         rChangeCurrRing(Rdest);
         ideal Idest = NULL;
         bool c = fglmzero(Rsrc, Isrc, Rdest, Idest, FALSE, FALSE);
-	     rChangeCurrRing(origin);
-	     return Idest;
+        rChangeCurrRing(origin);
+        return Idest;
     });
 }
diff --git a/src/module/module.jl b/src/module/module.jl
@@ -258,13 +258,15 @@ end
 
 @doc Markdown.doc"""
     lift(M::smodule, SM::smodule)
-> represents the generators of SM in terms of the generators of M
-> (Matrix(SM) = Matrix(M)*matrix(result))
+> represents the generators of SM in terms of the generators of M.
+> Returns result, rest
+> (Matrix(SM) = (Matrix(M)-Matrix(rest))*matrix(result))
+> If SM is in M, rest is the null module
 """
 function lift(M::smodule, SM::smodule)
    R = base_ring(M)
-   ptr = libSingular.id_Lift(M.ptr, SM.ptr, R.ptr)
-   return Module(R, ptr)
+   ptr,rest_ptr = libSingular.id_Lift(M.ptr, SM.ptr, R.ptr)
+   return Module(R, ptr),Module(R,rest_ptr)
 end
 
 ###############################################################################

diff --git a/test/module/smodule-test.jl b/test/module/smodule-test.jl
@@ -170,9 +170,10 @@ end
    A = Singular.Module(R, v1, v2)
    B = Singular.Module(R, v1)
 
-   M = lift(A,B)
+   M,r = lift(A,B)
 
    @test M[1] == vector(R,R(1),R(0))
+   @test iszero(r[1])
 end
 
 @testset "smodule.eliminate..." begin