/*
  This code can be loaded, or copied and pasted, into Magma.
  It will load the data associated to the HMF, including
  the field, level, and Hecke and Atkin-Lehner eigenvalue data.
  At the *bottom* of the file, there is code to recreate the
  Hilbert modular form in Magma, by creating the HMF space
  and cutting out the corresponding Hecke irreducible subspace.
  From there, you can ask for more eigenvalues or modify as desired.
  It is commented out, as this computation may be lengthy.
*/

P<x> := PolynomialRing(Rationals());
g := P![7, 6, -5, -2, 1];
F<w> := NumberField(g);
ZF := Integers(F);

NN := ideal<ZF | {28, 14, -w^3 + w^2 + 3*w}>;

primesArray := [
[4, 2, -w^2 + w + 3],
[7, 7, w],
[7, 7, -w^2 + 2*w + 1],
[7, 7, w^2 - 2],
[7, 7, w - 1],
[23, 23, -w^3 + w^2 + 3*w - 1],
[23, 23, w^3 - 2*w^2 - 2*w + 2],
[31, 31, w^2 - 5],
[31, 31, -w^2 + 2*w + 4],
[41, 41, -w^3 + 2*w^2 + 2*w - 6],
[41, 41, w^3 - w^2 - 3*w - 3],
[47, 47, w^2 - 2*w - 5],
[47, 47, w^2 - 6],
[71, 71, -w^3 + 2*w^2 + 3*w - 1],
[71, 71, -w^3 + w^2 + 4*w - 3],
[79, 79, -w - 3],
[79, 79, w - 4],
[81, 3, -3],
[89, 89, w^2 - 3*w - 2],
[89, 89, w^2 + w - 4],
[97, 97, 2*w^3 - 5*w^2 - 4*w + 9],
[97, 97, -2*w^3 + w^2 + 8*w + 2],
[113, 113, w^3 - 2*w^2 - 4*w + 2],
[113, 113, w^3 - w^2 - 5*w + 3],
[121, 11, 2*w^2 - w - 9],
[121, 11, -2*w^2 + 3*w + 8],
[127, 127, w^3 - 3*w^2 - 2*w + 5],
[127, 127, w^3 - 5*w - 1],
[137, 137, 2*w - 1],
[167, 167, 2*w^3 - 2*w^2 - 7*w - 2],
[167, 167, w^3 - 7*w - 4],
[167, 167, 2*w^3 - w^2 - 9*w - 2],
[167, 167, 2*w^3 - 4*w^2 - 5*w + 9],
[191, 191, 2*w^3 - 4*w^2 - 5*w + 5],
[191, 191, -2*w^3 + 2*w^2 + 7*w - 2],
[193, 193, -2*w^3 + 3*w^2 + 6*w - 6],
[193, 193, -2*w^3 + 2*w^2 + 7*w - 4],
[193, 193, -2*w^3 + 4*w^2 + 5*w - 3],
[193, 193, 2*w^3 - 3*w^2 - 6*w + 1],
[199, 199, -w^3 - 2*w^2 + 6*w + 10],
[199, 199, -w^3 + 5*w^2 - w - 13],
[223, 223, -w^3 + 2*w^2 + 3*w - 8],
[223, 223, w^3 - w^2 - 4*w - 4],
[233, 233, -w^2 - 1],
[233, 233, w^2 - 2*w + 2],
[239, 239, 3*w^2 - 2*w - 13],
[239, 239, 3*w^2 - 4*w - 12],
[241, 241, w^3 - w^2 - 6*w + 3],
[241, 241, w^3 - 2*w^2 - 5*w + 3],
[257, 257, -w^3 + 3*w^2 + 4*w - 9],
[257, 257, -2*w^3 + 4*w^2 + 8*w - 11],
[257, 257, -w^3 + 2*w^2 + 4],
[257, 257, w^3 - 7*w - 3],
[263, 263, -w^3 + w^2 + 3*w + 5],
[263, 263, w^3 - 5*w^2 + 12],
[263, 263, -w^3 - 2*w^2 + 7*w + 8],
[263, 263, -w^3 + 7*w + 2],
[271, 271, -w^3 + 3*w^2 + 2*w - 3],
[271, 271, w^3 - 5*w + 1],
[289, 17, 3*w^2 - 3*w - 8],
[289, 17, 3*w^2 - 3*w - 10],
[311, 311, -2*w^3 + 2*w^2 + 7*w - 1],
[311, 311, -w^3 + 5*w^2 - w - 11],
[311, 311, w^3 + 2*w^2 - 6*w - 8],
[311, 311, -2*w^3 + 4*w^2 + 5*w - 6],
[337, 337, w^3 - w^2 - 2*w - 4],
[337, 337, 2*w^3 - 9*w - 4],
[337, 337, 2*w^3 - 6*w^2 - 3*w + 11],
[337, 337, -w^3 + 2*w^2 + w - 6],
[353, 353, -w^3 + 4*w^2 - 12],
[353, 353, w^3 + w^2 - 5*w - 9],
[359, 359, 2*w^3 - 4*w^2 - 6*w + 5],
[359, 359, 2*w^3 - 2*w^2 - 8*w + 3],
[361, 19, -w^3 + 5*w^2 - 13],
[361, 19, w^3 + 2*w^2 - 7*w - 9],
[367, 367, 2*w^3 - 10*w - 5],
[367, 367, w^3 - w^2 - 6*w + 2],
[367, 367, -w^3 + 2*w^2 + 5*w - 4],
[367, 367, 2*w^3 - 6*w^2 - 4*w + 13],
[401, 401, -w^3 + 2*w^2 + 5*w - 5],
[401, 401, -w^3 + w^2 + 6*w - 1],
[409, 409, 2*w^3 - 3*w^2 - 6*w + 4],
[409, 409, 3*w^3 - 3*w^2 - 12*w + 1],
[409, 409, -3*w^3 + 6*w^2 + 9*w - 11],
[409, 409, -2*w^3 + 3*w^2 + 6*w - 3],
[431, 431, 3*w^2 - 5*w - 10],
[431, 431, w^3 + w^2 - 8*w - 3],
[457, 457, -2*w^3 + 4*w^2 + 4*w - 5],
[457, 457, -2*w^3 + 2*w^2 + 6*w - 1],
[463, 463, -2*w^3 + 7*w^2 + w - 16],
[463, 463, 3*w^3 - 6*w^2 - 8*w + 8],
[503, 503, -w^3 + 3*w^2 + 2*w - 12],
[503, 503, -w^3 + 4*w^2 + 4*w - 10],
[521, 521, w^3 + w^2 - 6*w - 2],
[521, 521, -w^3 + 4*w^2 + w - 6],
[529, 23, w^2 - w - 8],
[569, 569, w^3 - 3*w - 6],
[569, 569, -w^3 + 3*w^2 - 8],
[577, 577, -w^3 + 4*w^2 - w - 10],
[577, 577, w^3 + w^2 - 4*w - 8],
[593, 593, -w^3 + 3*w^2 - 12],
[593, 593, w^3 - 3*w - 10],
[599, 599, w^3 + 3*w^2 - 7*w - 9],
[599, 599, -w^3 + 3*w^2 + 3*w - 13],
[601, 601, w^2 + 2*w - 4],
[601, 601, w^2 - 4*w - 1],
[607, 607, 2*w^2 - 13],
[607, 607, w^3 + 2*w^2 - 7*w - 5],
[607, 607, 2*w^3 - 3*w^2 - 8*w + 8],
[607, 607, 2*w^2 - 4*w - 11],
[617, 617, w^3 + w^2 - 9*w - 1],
[617, 617, w^3 - w^2 - 4*w - 5],
[617, 617, -w^3 + 2*w^2 + 3*w - 9],
[617, 617, -w^3 + 4*w^2 + 4*w - 8],
[625, 5, -5],
[631, 631, -w^3 + 5*w^2 - 2*w - 13],
[631, 631, w^3 + 2*w^2 - 5*w - 11],
[641, 641, w^2 - 2*w + 3],
[641, 641, -w^3 + 6*w - 2],
[641, 641, -w^3 + 3*w^2 + 3*w - 3],
[641, 641, -w^2 - 2],
[647, 647, -2*w^3 + 5*w^2 + 4*w - 6],
[647, 647, 2*w^3 - 4*w^2 - 5*w - 1],
[647, 647, 3*w^3 - 7*w^2 - 7*w + 13],
[647, 647, -2*w^3 + w^2 + 8*w - 1],
[673, 673, -w^3 + 7*w - 2],
[673, 673, -w^3 + 3*w^2 + 4*w - 4],
[719, 719, -2*w^3 + 5*w^2 + 3*w - 12],
[719, 719, 4*w^2 - 5*w - 10],
[719, 719, -4*w^2 + 3*w + 11],
[719, 719, 2*w^3 - w^2 - 7*w - 6],
[727, 727, -w - 5],
[727, 727, w - 6],
[743, 743, w^2 + 2*w - 11],
[743, 743, w^3 + 4*w^2 - 11*w - 11],
[751, 751, -2*w^2 + w + 13],
[751, 751, 2*w^2 - 3*w - 12],
[769, 769, 2*w^3 - 6*w^2 - 3*w + 17],
[769, 769, 3*w^3 - 2*w^2 - 11*w + 2],
[809, 809, w^3 + 3*w^2 - 6*w - 11],
[809, 809, -3*w^3 + 5*w^2 + 8*w - 11],
[823, 823, -w^3 + w^2 + 2*w - 6],
[823, 823, 4*w^2 - 5*w - 11],
[823, 823, -4*w^2 + 3*w + 12],
[823, 823, -w^3 + 4*w^2 + 4*w - 12],
[839, 839, -2*w^3 + w^2 + 6*w + 5],
[839, 839, -3*w^3 + 8*w^2 + 7*w - 17],
[839, 839, 3*w^3 - w^2 - 14*w - 5],
[839, 839, -2*w^3 + 5*w^2 + 2*w - 10],
[857, 857, w^3 + w^2 - 8*w - 2],
[857, 857, -w^3 + 4*w^2 + 3*w - 8],
[863, 863, -w^3 + w^2 - w - 1],
[863, 863, w^3 - 2*w^2 + 2*w - 2],
[911, 911, -w^3 + 3*w^2 - 11],
[911, 911, w^3 - 3*w - 9],
[919, 919, -2*w^3 + w^2 + 8*w - 2],
[919, 919, -2*w^3 + 5*w^2 + 4*w - 5],
[929, 929, -2*w^3 + 2*w^2 + 9*w - 4],
[929, 929, 2*w^3 - 9*w - 12],
[929, 929, 2*w^3 - 6*w^2 - 3*w + 19],
[929, 929, -2*w^3 + 4*w^2 + 7*w - 5],
[937, 937, -w^3 + 2*w^2 - 6],
[937, 937, -w^3 + 3*w^2 - 10],
[937, 937, w^3 - 3*w - 8],
[937, 937, w^3 - w^2 - w - 5],
[953, 953, 2*w^3 - 6*w^2 - 3*w + 18],
[953, 953, -3*w^3 + 3*w^2 + 11*w - 5],
[961, 31, 4*w^2 - 4*w - 11],
[967, 967, -w^3 + 7*w - 3],
[967, 967, -2*w^3 + 2*w^2 + 11*w + 2],
[967, 967, -w^3 - 4*w^2 + 9*w + 9],
[967, 967, -w^3 + 3*w^2 + 4*w - 3],
[977, 977, 2*w^2 - 5*w - 8],
[977, 977, -w^3 + 2*w^2 - w + 6],
[977, 977, -w^3 + w^2 - 6],
[977, 977, 2*w^2 + w - 11],
[983, 983, -w^3 + 6*w^2 - 2*w - 16],
[983, 983, w^3 + 3*w^2 - 7*w - 13]];
primes := [ideal<ZF | {F!x : x in I}> : I in primesArray];

heckePol := x^3 - 3*x^2 - 10*x - 4;
K<e> := NumberField(heckePol);

heckeEigenvaluesArray := [-1, -1, e, 1/2*e^2 - 5/2*e - 4, -e, e^2 - 4*e - 2, -3/2*e^2 + 15/2*e + 7, -e - 2, 3/2*e^2 - 9/2*e - 11, 3/2*e^2 - 13/2*e - 5, -3/2*e^2 + 17/2*e + 8, e^2 - 3*e + 2, 3/2*e^2 - 11/2*e - 10, 2*e^2 - 6*e - 8, 1/2*e^2 - 5/2*e + 1, -1/2*e^2 - 1/2*e + 9, -3*e^2 + 11*e + 18, 1/2*e^2 + 1/2*e - 7, -4*e^2 + 17*e + 24, e^2 - 5*e - 2, -e^2 + 4*e + 4, 4*e^2 - 18*e - 22, 3*e^2 - 15*e - 20, 5/2*e^2 - 25/2*e - 8, -9/2*e^2 + 31/2*e + 26, -2*e - 4, -2*e^2 + 11*e + 8, 1/2*e^2 - 1/2*e - 1, 4*e^2 - 16*e - 18, -5/2*e^2 + 9/2*e + 26, 1/2*e^2 - 3/2*e - 4, 1/2*e^2 - 3/2*e - 4, -1/2*e^2 + 1/2*e - 11, 5/2*e^2 - 19/2*e - 10, -2*e^2 + 8*e + 20, 3/2*e^2 - 21/2*e - 3, -3*e^2 + 10*e + 26, -2*e^2 + 2*e + 26, -e^2 + 2*e - 2, -3/2*e^2 + 13/2*e - 9, -5/2*e^2 + 5/2*e + 28, 5/2*e^2 - 19/2*e - 13, 1/2*e^2 - 9/2*e + 16, -e^2 + 7*e, -13/2*e^2 + 49/2*e + 35, -13/2*e^2 + 49/2*e + 35, 1/2*e^2 - 9/2*e - 4, -7*e^2 + 25*e + 38, 2*e + 10, 5/2*e^2 - 17/2*e - 8, 2*e - 6, -5/2*e^2 + 7/2*e + 24, -6*e + 14, -3*e^2 + 8*e + 20, e^2 + e - 10, -1/2*e^2 - 9/2*e + 12, 4*e^2 - 14*e - 16, -9/2*e^2 + 35/2*e + 39, 13/2*e^2 - 49/2*e - 34, 2*e^2 - 11*e - 10, 11/2*e^2 - 31/2*e - 36, -11/2*e^2 + 45/2*e + 31, -1/2*e^2 + 7/2*e + 19, -3*e^2 + 15*e + 28, 2*e^2 - 11*e - 4, 2*e^2 - 9*e - 2, -3*e^2 + 8*e + 18, -1/2*e^2 + 5/2*e + 20, 9/2*e^2 - 39/2*e - 19, 17/2*e^2 - 65/2*e - 52, 7*e^2 - 22*e - 40, -e^2 + 7*e + 26, 3/2*e^2 - 15/2*e - 18, -7/2*e^2 + 23/2*e + 14, 7/2*e^2 - 25/2*e - 6, -3/2*e^2 + 23/2*e + 10, 1/2*e^2 - 5/2*e + 25, 5/2*e^2 - 13/2*e - 12, -17/2*e^2 + 67/2*e + 46, -7*e^2 + 29*e + 50, 2*e^2 - 9*e + 14, -3*e^2 + 12*e + 18, 3*e^2 - 8*e - 8, -e^2 + 9*e - 6, 1/2*e^2 - 1/2*e + 12, -5*e^2 + 18*e + 12, 6*e^2 - 21*e - 26, 11/2*e^2 - 49/2*e - 37, -2*e^2 + 7*e + 14, 6*e^2 - 23*e - 26, e^2 + 3*e - 32, 4*e^2 - 12*e - 12, -11/2*e^2 + 47/2*e + 17, 7*e^2 - 29*e - 42, 5*e^2 - 13*e - 42, -5/2*e^2 + 15/2*e + 8, 19/2*e^2 - 67/2*e - 59, 2*e^2 - 2*e - 8, 1/2*e^2 + 21/2*e - 27, 4*e - 2, -8*e^2 + 34*e + 48, -3*e^2 + 15*e - 2, 2*e^2 - 4*e + 8, 4*e^2 - 15*e - 32, -11/2*e^2 + 49/2*e + 27, -5/2*e^2 + 13/2*e + 38, 1/2*e^2 + 1/2*e + 1, -6*e^2 + 25*e + 32, -5*e^2 + 17*e + 32, -1/2*e^2 - 3/2*e + 22, -1/2*e^2 + 3/2*e - 19, -17/2*e^2 + 67/2*e + 45, 17/2*e^2 - 65/2*e - 43, -5/2*e^2 + 13/2*e + 10, 6*e^2 - 30*e - 40, -9/2*e^2 + 41/2*e + 4, 7*e^2 - 21*e - 46, 5*e^2 - 21*e - 22, 13/2*e^2 - 55/2*e - 17, -19/2*e^2 + 69/2*e + 39, 2*e^2 - 12*e - 20, -4*e^2 + 10*e + 38, e^2 - 26, -9*e^2 + 40*e + 58, 2*e^2 - 7*e + 26, 8*e^2 - 33*e - 44, 9/2*e^2 - 47/2*e - 14, -4*e - 16, 6*e^2 - 28*e - 26, -13/2*e^2 + 41/2*e + 32, 3/2*e^2 - 3/2*e - 14, 4*e^2 - 12*e - 4, -6*e^2 + 18*e + 42, -3*e^2 + 4*e + 50, -3*e^2 + 8*e + 18, e^2 + e - 26, -21/2*e^2 + 91/2*e + 59, -7*e^2 + 28*e + 22, -15/2*e^2 + 75/2*e + 37, 8*e^2 - 22*e - 50, -5/2*e^2 + 25/2*e - 8, -17/2*e^2 + 57/2*e + 41, 9/2*e^2 - 31/2*e - 56, -10, 11/2*e^2 - 47/2*e - 26, -e^2 - e - 2, -7/2*e^2 + 13/2*e + 49, 21/2*e^2 - 83/2*e - 50, -3*e^2 + 17*e - 18, 3*e^2 - 15*e - 22, 4*e^2 - 24*e - 14, 11*e^2 - 42*e - 52, -25/2*e^2 + 99/2*e + 71, -9/2*e^2 + 19/2*e + 35, -6*e^2 + 27*e + 50, 21/2*e^2 - 73/2*e - 41, -4*e^2 + 6*e + 16, -19/2*e^2 + 81/2*e + 39, -9/2*e^2 + 59/2*e + 6, -8*e^2 + 23*e + 46, 11/2*e^2 - 53/2*e - 31, -3*e^2 + 7*e + 2, 3*e^2 - 15*e - 48, 13*e^2 - 62*e - 76, -7/2*e^2 + 23/2*e - 2, -1/2*e^2 - 9/2*e + 47, -7/2*e^2 + 17/2*e + 17, 4*e^2 - 17*e - 40, -40, 1/2*e^2 - 9/2*e + 46, -7*e^2 + 29*e + 22, 7/2*e^2 - 17/2*e - 19, 3*e^2 - 5*e - 32, -2*e^2 + 7*e - 12, 1/2*e^2 + 1/2*e - 2, -15/2*e^2 + 47/2*e + 58, 7/2*e^2 - 31/2*e + 10, 21/2*e^2 - 65/2*e - 66];
heckeEigenvalues := AssociativeArray();
for i := 1 to #heckeEigenvaluesArray do
  heckeEigenvalues[primes[i]] := heckeEigenvaluesArray[i];
end for;

ALEigenvalues := AssociativeArray();
ALEigenvalues[ideal<ZF | {4, 2, -w^2 + w + 3}>] := 1;
ALEigenvalues[ideal<ZF | {7, 7, w}>] := 1;

// EXAMPLE:
// pp := Factorization(2*ZF)[1][1];
// heckeEigenvalues[pp];

print "To reconstruct the Hilbert newform f, type
  f, iso := Explode(make_newform());";

function make_newform();
 M := HilbertCuspForms(F, NN);
 S := NewSubspace(M);
 // SetVerbose("ModFrmHil", 1);
 NFD := NewformDecomposition(S);
 newforms := [* Eigenform(U) : U in NFD *];

 if #newforms eq 0 then;
  print "No Hilbert newforms at this level";
  return 0;
 end if;

 print "Testing ", #newforms, " possible newforms";
 newforms := [* f: f in newforms | IsIsomorphic(BaseField(f), K) *];
 print #newforms, " newforms have the correct Hecke field";

 if #newforms eq 0 then;
  print "No Hilbert newform found with the correct Hecke field";
  return 0;
 end if;

 autos := Automorphisms(K);
 xnewforms := [* *];
 for f in newforms do;
  if K eq RationalField() then;
   Append(~xnewforms, [* f, autos[1] *]);
  else;
   flag, iso := IsIsomorphic(K,BaseField(f));
   for a in autos do;
    Append(~xnewforms, [* f, a*iso *]);
   end for;
  end if;
 end for;
 newforms := xnewforms;

 for P in primes do;
  xnewforms := [* *];
  for f_iso in newforms do;
   f, iso := Explode(f_iso);
   if HeckeEigenvalue(f,P) eq iso(heckeEigenvalues[P]) then;
    Append(~xnewforms, f_iso);
   end if;
  end for;
  newforms := xnewforms;
  if #newforms eq 0 then;
   print "No Hilbert newform found which matches the Hecke eigenvalues";
   return 0;
  else if #newforms eq 1 then;
   print "success: unique match";
   return newforms[1];
  end if;
  end if;
 end for;
 print #newforms, "Hilbert newforms found which match the Hecke eigenvalues";
 return newforms[1];

end function;