magma check works

parent 84708df2
// In this file, we provide some magma functions to test that the output of rrspace is correct.
RRSPACE_PATH="/users/pspaenle/repos/rrspace"
RRSPACE_PATH :="/users/pspaenle/repos/rrspace";
RRSPACE_TMP_INFILE :="/tmp/tmpin.rrspace";
RRSPACE_TMP_OUTFILE :="/tmp/tmpout.rrspace";
// Given a function f and a finite set B of functions on a curve, check if the k-vector space generated by B
// contains f
......@@ -17,11 +19,7 @@ function CheckBelongsSpan(f, B)
lM := [];
lv := [];
for i in [1..nbtests] do
repeat
P := Random(C);
until P ne Infinity() and
&and[Evaluate(g, P) ne Infinity() : g in B] and
Evaluate(f, P) ne Infinity();
P := RandomPlace(C, 1);
lM cat:= [Evaluate(g, P) : g in B];
lv cat:= [Evaluate(f, P)];
end for;
......@@ -36,22 +34,154 @@ function CheckEqualSpan(B1, B2)
end function;
// Set variable order y > x > z
// Ambient space of the curve should be the projective space
function Check_rrspace(C, D)
// first compute the input representation for rrspace
K := BaseRing(C);
assert Type(K) eq FldFin;
assert AmbientSpace(C) eq ProjectiveSpace(K, 2);
Dp, Dm := SignDecomposition(D);
Ip := Ideal(Dp);
Im := Ideal(Dm);
R := Universe(Generators(Ip));
Gp := GroebnerBasis(ChangeOrder(Ip+Ideal(R.3-1), "lex"));
Gm := GroebnerBasis(ChangeOrder(Im+Ideal(R.3-1), "lex"));
R := PolynomialRing(K, 3);
eqnC := R!Equation(C);
eqnC /:= LeadingCoefficient(eqnC);
assert LeadingMonomial(eqnC) eq R.1^Degree(C);
Is := Ideal([Derivative(eqnC, 1), Derivative(eqnC, 2), Derivative(eqnC, 3), R.3-1]); // There should not be any node at infinity
Gp := GroebnerBasis(Ideal([R!g : g in Generators(Ip)] cat [R.3-1]));
Gm := GroebnerBasis(Ideal([R!g : g in Generators(Im)] cat [R.3-1]));
Gs := GroebnerBasis(Is);
assert(Degree(Gp[2]) eq Degree(Ip));
assert(Degree(Gm[2]) eq Degree(Im));
assert(Gm eq [1] or Degree(Gm[2]) eq Degree(Im));
assert(Gs eq [1] or Degree(Gs[2]) eq Dimension(R/Is));
if Gm eq [1] then
Gm := [R!0, R!1];
end if;
if Gs eq [1] then
Gs := [R!0, R!1];
end if;
Runiv := PolynomialRing(K);
fp := Evaluate( Gp[2], [0, Runiv.1, 0]);
gp := Evaluate(-Gp[1], [0, Runiv.1, 0]);
fm := Evaluate( Gm[2], [0, Runiv.1, 0]);
gm := Evaluate(-Gm[1], [0, Runiv.1, 0]);
fs := Evaluate( Gs[2], [0, Runiv.1, 0]);
gs := Evaluate(-Gs[1], [0, Runiv.1, 0]);
// Write input file for rrspace
SetOutputFile(RRSPACE_TMP_INFILE : Overwrite := true);
printf "%o\n", #K;
printf "[ %o ", Degree(C);
tmp_eqn := eqnC;
for i in [0..Degree(C)] do
tmp_c := Evaluate(tmp_eqn, [0, Runiv.1, 1])/Factorial(i);
tmp_eqn := Derivative(tmp_eqn, 1);
printf "[";
lc := Eltseq(tmp_c);
for j in [1..#lc] do
printf "%o", lc[j];
if j ne #lc then
printf " ";
end if;
end for;
printf "] ";
end for;
printf " ]\n";
printf "< [";
lc := Eltseq(fs);
for j in [1..#lc] do
printf "%o", lc[j];
if j ne #lc then
printf " ";
end if;
end for;
printf "] ";
printf "[";
lc := Eltseq(gs);
for j in [1..#lc] do
printf "%o", lc[j];
if j ne #lc then
printf " ";
end if;
end for;
printf "] ";
printf ">\n";
printf "{ < [";
lc := Eltseq(fp);
for j in [1..#lc] do
printf "%o", lc[j];
if j ne #lc then
printf " ";
end if;
end for;
printf "] ";
printf "[";
lc := Eltseq(gp);
for j in [1..#lc] do
printf "%o", lc[j];
if j ne #lc then
printf " ";
else
printf "] ";
end if;
end for;
printf "> < [";
lc := Eltseq(fm);
for j in [1..#lc] do
printf "%o", lc[j];
if j ne #lc then
printf " ";
end if;
end for;
printf "] ";
printf "[";
lc := Eltseq(gm);
for j in [1..#lc] do
printf "%o", lc[j];
if j ne #lc then
printf " ";
end if;
end for;
printf "] ";
printf "> }\n";
UnsetOutputFile();
// Compute with rrspace
System(RRSPACE_PATH cat
"/rrspace -c < " cat
RRSPACE_TMP_INFILE cat
" > " cat
RRSPACE_TMP_OUTFILE);
FF<y,x> := FunctionField(C);
basis_rrspace := eval Read(RRSPACE_TMP_OUTFILE);
vs_rr, phi := RiemannRochSpace(D);
print Dimension(vs_rr), #basis_rrspace;
// print basis_rrspace;
return Dimension(vs_rr) eq #basis_rrspace and
CheckEqualSpan([phi(b) : b in Basis(vs_rr)], basis_rrspace);
end function;
K := GF(1009);
R<Y,X,Z> := PolynomialRing(K, 3);
Q := &+[Random(K) * m : m in MonomialsOfDegree(R, 4)];
C := Curve(ProjectiveSpace(K, 2), Q);
D := Divisor(RandomPlace(C, 5));
Check_rrspace(C, D);
K := GF(1009);
R<Y,X,Z> := PolynomialRing(K, 3);
Q := - Y^2*Z^2 + X^2*Z^2 + Y^4 -X^3*Z;
C := Curve(ProjectiveSpace(K, 2), Q);
D := Divisor(RandomPlace(C, 5));
Check_rrspace(C, D);
......@@ -21,11 +21,12 @@ Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#include <iostream>
#include <sstream>
#include "algos.h"
#include <unistd.h>
using namespace NTL;
using namespace std;
int main() {
int main(int argc, char** argv) {
long p;
BivPol eq_curve;
cin >> p;
......@@ -42,12 +43,39 @@ int main() {
RRspace basisRR = RiemannRochBasis(D, E);
bool MAGMACHECK_FLAG = false;
int c;
while ((c = getopt(argc, argv, "chvo:s:")) != -1)
switch (c) {
case 'c':
MAGMACHECK_FLAG = true;
break;
default:
std::cerr << "option not recognized, aborting." << std::endl;
abort();
}
if (!MAGMACHECK_FLAG) {
cout << "Dimension: " << basisRR.num_basis.size() << endl;
cout << "Denominator: " << endl;
PrintMagma(std::cout, basisRR.denom) << endl;
cout << "Numerators: " << endl;
for (size_t i = 0; i < basisRR.num_basis.size(); ++i)
PrintMagma(std::cout, basisRR.num_basis[i]) << endl;
return 0;
} else {
cout << "[" << endl;
for (size_t i = 0; i < basisRR.num_basis.size(); ++i) {
cout << "(";
PrintMagma(std::cout, basisRR.num_basis[i]);
cout << ")/(";
PrintMagma(std::cout, basisRR.denom);
cout << ")";
if (i != basisRR.num_basis.size()-1)
cout << ",";
cout << endl;
}
cout << "]" << endl;
}
return EXIT_SUCCESS;
}
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