
// Make newform 1470.2.g.k in Magma, downloaded from the LMFDB on 19 April 2024.
// To make the character of type GrpDrchElt, type "MakeCharacter_1470_g();"
// To make the character of type GrpDrchElt with Codomain the HeckeField, type "MakeCharacter_1470_g_Hecke();"
// To make the coeffs of the qexp of the newform in the Hecke field type "qexpCoeffs();"
// To make the newform (type ModFrm), type "MakeNewformModFrm_1470_2_g_k();".
// This may take a long time!  To see verbose output, uncomment the SetVerbose lines below.
// The precision argument determines an initial guess on how many Fourier coefficients to use.
// This guess is increased enough to uniquely determine the newform.
// To make the Hecke irreducible modular symbols subspace (type ModSym)
// containing the newform, type "MakeNewformModSym_1470_2_g_k();".
// This may take a long time!  To see verbose output, uncomment the SetVerbose line below.
// The default sign is -1.  You can change this with the optional parameter "sign".
function ConvertToHeckeField(input: pass_field := false, Kf := [])
    if not pass_field then
        poly := [64, 0, 176, 0, 97, 0, 18, 0, 1];
        Kf := NumberField(Polynomial([elt : elt in poly]));
        AssignNames(~Kf, ["nu"]);
    end if;
    Rf_num := [[1, 0, 0, 0, 0, 0, 0, 0], [80, -184, -2, -15, -20, 10, -2, 1], [0, -104, 0, -89, 0, -18, 0, -1], [-8, 0, 37, 0, 14, 0, 1, 0], [-80, -184, 2, -15, 20, 10, 2, 1], [0, 168, 0, 179, 0, 46, 0, 3], [336, 120, 358, 15, 92, -10, 6, -1], [336, -120, 358, -15, 92, 10, 6, 1]];
    Rf_basisdens := [1, 64, 32, 16, 64, 64, 64, 64];
    Rf_basisnums := ChangeUniverse([[z : z in elt] : elt in Rf_num], Kf);
    Rfbasis := [Rf_basisnums[i]/Rf_basisdens[i] : i in [1..Degree(Kf)]];
    inp_vec := Vector(Rfbasis)*ChangeRing(Transpose(Matrix([[elt : elt in row] : row in input])),Kf);
    return Eltseq(inp_vec);
end function;


// To make the character of type GrpDrchElt, type "MakeCharacter_1470_g();"
function MakeCharacter_1470_g()
    N := 1470;
    order := 2;
    char_gens := [491, 1177, 1081];
    v := [2, 1, 2];
    // chi(gens[i]) = zeta^v[i]
    assert UnitGenerators(DirichletGroup(N)) eq char_gens;
    F := CyclotomicField(order);
    chi := DirichletCharacterFromValuesOnUnitGenerators(DirichletGroup(N,F),[F|F.1^e:e in v]);
    return MinimalBaseRingCharacter(chi);
end function;

// To make the character of type GrpDrchElt with Codomain the HeckeField, type "MakeCharacter_1470_g_Hecke();"
function MakeCharacter_1470_g_Hecke(Kf)
    N := 1470;
    order := 2;
    char_gens := [491, 1177, 1081];
    char_values := [[1, 0, 0, 0, 0, 0, 0, 0], [-1, 0, 0, 0, 0, 0, 0, 0], [1, 0, 0, 0, 0, 0, 0, 0]];
    assert UnitGenerators(DirichletGroup(N)) eq char_gens;
    values := ConvertToHeckeField(char_values : pass_field := true, Kf := Kf); // the value of chi on the gens as elements in the Hecke field
    F := Universe(values);// the Hecke field
    chi := DirichletCharacterFromValuesOnUnitGenerators(DirichletGroup(N,F),values);
    return chi;
end function;


function ExtendMultiplicatively(weight, aps, character)
    prec := NextPrime(NthPrime(#aps)) - 1; // we will able to figure out a_0 ... a_prec
    primes := PrimesUpTo(prec);
    prime_powers := primes;
    assert #primes eq #aps;
    log_prec := Floor(Log(prec)/Log(2)); // prec < 2^(log_prec+1)
    F := Universe(aps);
    FXY<X, Y> := PolynomialRing(F, 2);
    // 1/(1 - a_p T + p^(weight - 1) * char(p) T^2) = 1 + a_p T + a_{p^2} T^2 + ...
    R<T> := PowerSeriesRing(FXY : Precision := log_prec + 1);
    recursion := Coefficients(1/(1 - X*T + Y*T^2));
    coeffs := [F!0: i in [1..(prec+1)]];
    coeffs[1] := 1; //a_1
    for i := 1 to #primes do
        p := primes[i];
        coeffs[p] := aps[i];
        b := p^(weight - 1) * F!character(p);
        r := 2;
        p_power := p * p;
        //deals with powers of p
        while p_power le prec do
            Append(~prime_powers, p_power);
            coeffs[p_power] := Evaluate(recursion[r + 1], [aps[i], b]);
            p_power *:= p;
            r +:= 1;
        end while;    
    end for;
    Sort(~prime_powers);
    for pp in prime_powers do
        for k := 1 to Floor(prec/pp) do
            if GCD(k, pp) eq 1 then
                coeffs[pp*k] := coeffs[pp]*coeffs[k];
            end if;
        end for;
    end for;
    return coeffs;
end function;


function qexpCoeffs()
    // To make the coeffs of the qexp of the newform in the Hecke field type "qexpCoeffs();"
    weight := 2;
    raw_aps := [[0, 0, 0, 0, 0, -1, 0, 0], [0, 0, 0, 0, 0, 1, 0, 0], [1, 0, 0, 0, 0, 0, 0, -1], [0, 0, 0, 0, 0, 0, 0, 0], [0, 1, 0, 1, -1, 0, 0, 0], [0, 0, -2, 0, 0, 0, -1, 1], [0, -1, -1, 0, -1, 0, -1, 1], [-2, -1, 0, -2, 1, 0, -1, -1], [0, 1, -2, 0, 1, 0, -1, 1], [4, 1, 0, -1, -1, 0, -2, -2], [4, 1, 0, 1, -1, 0, 0, 0], [0, 0, 3, 0, 0, 2, -1, 1], [2, 0, 0, 2, 0, 0, 1, 1], [0, 1, 1, 0, 1, 0, -2, 2], [0, 1, 1, 0, 1, -4, 2, -2], [0, 1, -2, 0, 1, 4, -1, 1], [-6, -1, 0, 4, 1, 0, 1, 1], [6, 0, 0, 0, 0, 0, -3, -3], [0, 1, -1, 0, 1, 0, 0, 0], [-2, 1, 0, -2, -1, 0, -3, -3], [0, 1, 2, 0, 1, -4, -2, 2], [4, 2, 0, -4, -2, 0, -2, -2], [0, -2, -2, 0, -2, 4, 0, 0], [-10, 0, 0, -4, 0, 0, -1, -1], [0, -1, 4, 0, -1, -4, -2, 2], [4, -3, 0, -4, 3, 0, 2, 2], [0, 2, 2, 0, 2, 0, 0, 0], [0, 2, 6, 0, 2, -4, 0, 0], [-2, -1, 0, 6, 1, 0, -1, -1], [0, -3, 8, 0, -3, 8, 1, -1], [0, 0, -6, 0, 0, 8, -2, 2], [2, -1, 0, 0, 1, 0, 1, 1], [0, 1, -6, 0, 1, -6, -1, 1], [2, 3, 0, 0, -3, 0, -3, -3], [0, 0, 0, -7, 0, 0, 1, 1], [2, 1, 0, -4, -1, 0, -1, -1], [0, 3, -4, 0, 3, 0, -4, 4], [0, 3, -5, 0, 3, -8, 2, -2], [0, -3, 3, 0, -3, -4, 4, -4], [0, -2, 2, 0, -2, 0, 1, -1], [4, 1, 0, 15, -1, 0, 2, 2], [6, 2, 0, -6, -2, 0, -3, -3], [-6, 1, 0, 4, -1, 0, 3, 3], [0, 0, 2, 0, 0, 0, 2, -2], [0, -3, -2, 0, -3, -4, 3, -3], [-16, -1, 0, -3, 1, 0, 2, 2], [-4, 2, 0, 6, -2, 0, 4, 4], [0, 0, -2, 0, 0, 0, 2, -2], [0, -2, 0, 0, -2, -4, 2, -2], [-14, 4, 0, 6, -4, 0, -1, -1], [0, -2, -8, 0, -2, 6, -2, 2], [-2, 3, 0, -8, -3, 0, 1, 1], [0, -2, 0, 1, 2, 0, 0, 0], [0, -2, 0, 8, 2, 0, -2, -2], [0, -5, 9, 0, -5, 8, -1, 1], [0, 3, -6, 0, 3, 0, 1, -1], [-6, -6, 0, 0, 6, 0, -1, -1], [4, 1, 0, 9, -1, 0, 4, 4], [0, -3, -1, 0, -3, 8, 0, 0], [-18, 1, 0, 6, -1, 0, 1, 1], [0, 3, 6, 0, 3, -4, 5, -5], [0, 0, 4, 0, 0, -16, 3, -3], [0, 4, 8, 0, 4, -4, 0, 0], [-4, -2, 0, -8, 2, 0, -2, -2], [0, -7, 6, 0, -7, 4, -2, 2], [0, -1, 0, 0, -1, -4, -1, 1], [-4, -2, 0, -10, 2, 0, -4, -4], [0, 1, -2, 0, 1, 18, 3, -3], [0, 4, 8, 0, 4, -4, 0, 0], [6, -2, 0, 10, 2, 0, -3, -3], [0, -1, -1, 0, -1, -8, 3, -3], [-6, 3, 0, 2, -3, 0, 3, 3], [0, -2, 12, 0, -2, 0, 6, -6], [0, -1, -1, 0, -1, -16, 2, -2], [12, 8, 0, -4, -8, 0, 0, 0], [0, 1, -13, 0, 1, 4, -4, 4], [-8, -3, 0, 13, 3, 0, 0, 0], [0, 1, -12, 0, 1, 16, 2, -2], [-2, -1, 0, 4, 1, 0, 1, 1], [0, 4, 0, -7, -4, 0, -4, -4], [4, 0, 0, -16, 0, 0, 0, 0], [2, -6, 0, 2, 6, 0, 0, 0], [-22, -1, 0, -2, 1, 0, 3, 3], [0, 5, -8, 0, 5, -12, -6, 6], [-20, -3, 0, 1, 3, 0, 4, 4], [0, 2, 0, 0, 2, 4, 2, -2], [-2, -4, 0, -6, 4, 0, -2, -2], [0, -4, 10, 0, -4, 16, 6, -6], [-14, -2, 0, 8, 2, 0, 3, 3], [0, 0, 20, 0, 0, -8, 4, -4], [0, 2, 6, 0, 2, -12, -4, 4], [-4, 6, 0, 16, -6, 0, -2, -2], [0, -2, 14, 0, -2, 16, 0, 0], [-4, 3, 0, 9, -3, 0, 2, 2], [0, -2, 0, -12, 2, 0, -2, -2], [0, 1, 15, 0, 1, -4, 0, 0], [-12, 1, 0, -4, -1, 0, -2, -2], [10, 4, 0, -8, -4, 0, -3, -3], [0, 5, -2, 0, 5, -4, -1, 1], [6, -4, 0, -2, 4, 0, 2, 2], [0, -1, -11, 0, -1, 24, -8, 8], [0, -5, -4, 0, -5, 4, -1, 1], [0, -2, 10, 0, -2, -4, 0, 0], [-14, -3, 0, -8, 3, 0, -1, -1], [0, -6, 0, -8, 6, 0, 2, 2], [0, -1, 18, 0, -1, 12, 0, 0], [0, 0, 6, 0, 0, 20, 2, -2], [0, 3, 7, 0, 3, -8, 7, -7], [6, -5, 0, -4, 5, 0, -7, -7], [8, -6, 0, -1, 6, 0, 0, 0], [0, 4, -26, 0, 4, -16, -2, 2], [0, -8, -5, 0, -8, 2, -1, 1], [0, -3, 6, 0, -3, -10, -9, 9], [-6, 1, 0, 6, -1, 0, 1, 1], [6, 7, 0, 4, -7, 0, -3, -3], [14, 7, 0, 4, -7, 0, -7, -7], [0, -5, 6, 0, -5, -12, -3, 3], [0, 1, 7, 0, 1, 4, -4, 4], [0, -4, 4, 0, -4, -2, 0, 0], [0, -3, 0, -3, 3, 0, 0, 0], [-2, -2, 0, 16, 2, 0, 1, 1], [0, 3, 4, 0, 3, -22, -5, 5], [0, 4, 2, 0, 4, 16, 3, -3], [0, -8, -2, 0, -8, 4, -2, 2], [6, -11, 0, -4, 11, 0, -1, -1], [4, -11, 0, -13, 11, 0, -2, -2], [22, 1, 0, 8, -1, 0, -9, -9], [8, -6, 0, -2, 6, 0, 0, 0], [0, -10, 6, 0, -10, 16, 0, 0], [0, 5, 4, 0, 5, -24, 0, 0], [8, -2, 0, -4, 2, 0, -6, -6], [0, 0, 0, 0, 0, 0, -12, 12], [-6, -7, 0, 4, 7, 0, -1, -1], [0, -6, 13, 0, -6, 30, 3, -3], [-18, -4, 0, -4, 4, 0, -1, -1], [12, -4, 0, 3, 4, 0, 2, 2], [0, 6, -4, 0, 6, -16, 1, -1], [0, -4, 8, 0, -4, 12, 0, 0], [0, 0, -6, 0, 0, 32, 3, -3], [-18, 4, 0, -10, -4, 0, 2, 2], [-6, 11, 0, 8, -11, 0, 1, 1], [4, -8, 0, -7, 8, 0, -7, -7], [0, 6, -8, 0, 6, -8, 6, -6], [0, 10, -12, 0, 10, -28, -2, 2], [2, -6, 0, -12, 6, 0, -1, -1], [-4, 4, 0, -10, -4, 0, 2, 2], [0, -7, -4, 0, -7, -16, -2, 2], [0, -1, -7, 0, -1, 16, 3, -3], [18, -1, 0, 12, 1, 0, -3, -3], [0, -4, 0, 0, -4, 24, -4, 4], [0, -4, -7, 0, -4, 6, -7, 7], [10, -2, 0, 2, 2, 0, 5, 5], [0, -9, 5, 0, -9, 16, -4, 4], [0, 5, 17, 0, 5, -4, 2, -2], [0, 9, 11, 0, 9, -16, 4, -4], [14, -5, 0, -16, 5, 0, 1, 1], [18, -3, 0, 0, 3, 0, 3, 3], [6, 6, 0, -8, -6, 0, -1, -1], [0, 7, 8, 0, 7, 4, -6, 6], [-4, 9, 0, 0, -9, 0, 6, 6], [0, -4, -2, 0, -4, -12, 6, -6], [0, 8, -6, 0, 8, 0, 2, -2], [0, 0, 12, 0, 0, 40, 0, 0], [0, 10, 0, 0, -10, 0, -2, -2], [0, 6, -8, 0, 6, -2, 6, -6], [0, 5, 17, 0, 5, -4, 2, -2], [2, -3, 0, 0, 3, 0, -5, -5], [0, -1, 12, 0, -1, 24, -2, 2], [-4, 9, 0, 4, -9, 0, -9, -9], [0, 0, -10, 0, 0, -16, 1, -1], [0, 7, 0, -9, -7, 0, 4, 4], [10, 2, 0, -2, -2, 0, -5, -5], [10, 13, 0, -4, -13, 0, -1, -1], [0, 11, 2, 0, 11, 10, -7, 7], [12, -1, 0, -17, 1, 0, 0, 0], [-2, -6, 0, 4, 6, 0, 7, 7], [-16, 4, 0, -2, -4, 0, 10, 10], [-8, -5, 0, 7, 5, 0, 4, 4], [0, 6, -6, 0, 6, 0, 8, -8], [38, -2, 0, 0, 2, 0, -3, -3], [0, -2, 6, 0, -2, 32, 8, -8], [26, 3, 0, 12, -3, 0, -3, -3], [0, -4, 9, 0, -4, -6, 9, -9], [0, -1, 11, 0, -1, 24, 3, -3], [0, 5, -6, 0, 5, 0, 7, -7], [-10, 0, 0, 4, 0, 0, 9, 9], [0, -1, -19, 0, -1, 0, 0, 0], [0, -7, 2, 0, -7, -4, 3, -3], [-2, 7, 0, 20, -7, 0, 9, 9], [8, 2, 0, 18, -2, 0, -4, -4], [0, -1, 28, 0, -1, 20, 2, -2], [0, 12, 6, 0, 12, 4, 2, -2], [12, -4, 0, -4, 4, 0, 8, 8], [-6, 2, 0, 16, -2, 0, 7, 7], [0, -6, 18, 0, -6, 20, -4, 4], [0, 3, 23, 0, 3, -24, 3, -3], [-4, 6, 0, 0, -6, 0, 2, 2], [0, -12, 19, 0, -12, 30, 3, -3], [0, 7, 9, 0, 7, -16, 5, -5], [0, -3, 7, 0, -3, 20, -4, 4], [-8, 0, 0, -17, 0, 0, -9, -9], [0, -15, 0, -5, 15, 0, 2, 2], [0, -6, -22, 0, -6, 24, -11, 11], [36, 0, 0, -5, 0, 0, -6, -6], [8, 2, 0, -16, -2, 0, -10, -10], [0, 4, 4, 0, 4, 0, -5, 5], [12, 9, 0, 13, -9, 0, 4, 4], [0, 2, 4, 0, 2, -28, 2, -2], [-14, -2, 0, 0, 2, 0, 10, 10], [-14, -9, 0, -8, 9, 0, 1, 1], [0, 5, 4, 0, 5, 6, -11, 11], [-10, 4, 0, -16, -4, 0, -3, -3], [0, 4, -12, 0, 4, 0, -4, 4], [0, -8, 6, 0, -8, -20, -2, 2], [28, -4, 0, 6, 4, 0, -2, -2], [-12, 2, 0, 3, -2, 0, 2, 2], [0, -2, 22, 0, -2, -16, -4, 4], [-34, -4, 0, -18, 4, 0, -1, -1], [0, -1, -18, 0, -1, -8, 1, -1], [0, -6, 0, 0, -6, 14, 2, -2], [-2, 5, 0, -12, -5, 0, 7, 7], [8, 5, 0, -9, -5, 0, 2, 2], [-2, 4, 0, 34, -4, 0, -2, -2], [0, 4, -10, 0, 4, -24, -10, 10], [0, 0, -2, 0, 0, -20, -6, 6], [38, -11, 0, -8, 11, 0, -5, -5], [0, -9, -7, 0, -9, 24, -1, 1], [-14, 5, 0, -12, -5, 0, 3, 3], [0, -12, -16, 0, -12, -24, 4, -4], [4, -1, 0, -3, 1, 0, 6, 6], [0, -12, 13, 0, -12, 18, 5, -5], [14, 3, 0, 2, -3, 0, 3, 3], [-16, -4, 0, 4, 4, 0, 4, 4], [6, -2, 0, 16, 2, 0, -6, -6], [0, -4, -8, 0, -4, 12, 12, -12], [0, 3, -25, 0, 3, -4, -2, 2], [0, 0, 0, 39, 0, 0, 4, 4], [0, 7, -6, 0, 7, 20, -7, 7], [-4, -5, 0, 17, 5, 0, 2, 2], [-24, 2, 0, 2, -2, 0, -4, -4], [0, -6, -10, 0, -6, 12, -12, 12], [10, 9, 0, 18, -9, 0, -3, -3], [0, 10, -20, 0, 10, -16, 6, -6], [-22, -2, 0, 6, 2, 0, 16, 16], [0, 3, -7, 0, 3, 40, -1, 1], [24, 2, 0, -6, -2, 0, 0, 0], [0, 2, 10, 0, 2, -16, 8, -8], [26, -5, 0, -8, 5, 0, -3, -3], [12, -6, 0, -26, 6, 0, -8, -8], [0, -12, 0, 0, -12, -8, 4, -4], [0, 9, -17, 0, 9, 0, 4, -4], [-18, -4, 0, 14, 4, 0, -5, -5], [0, 4, -4, 0, 4, -8, 0, 0], [4, -2, 0, 15, 2, 0, -2, -2], [0, 0, -4, 0, 0, -16, -7, 7], [-28, -3, 0, -5, 3, 0, 2, 2], [18, 1, 0, -2, -1, 0, -3, -3], [0, 5, 6, 0, 5, -36, -5, 5], [0, -14, 4, 0, -14, 16, 5, -5], [0, 9, -12, 0, 9, -4, 4, -4], [0, -4, -24, 0, -4, -8, -8, 8], [0, -4, 12, 0, -4, -28, 4, -4], [10, -4, 0, -16, 4, 0, 3, 3], [0, 6, 22, 0, 6, -8, 7, -7], [0, 5, 5, 0, 5, 0, 9, -9], [34, 3, 0, -16, -3, 0, 1, 1], [-24, 6, 0, 9, -6, 0, 3, 3], [-10, 0, 0, -20, 0, 0, -1, -1], [0, -3, -1, 0, -3, -24, -12, 12], [0, 10, 18, 0, 10, -46, 12, -12], [-10, -2, 0, -22, 2, 0, 5, 5], [0, -3, 29, 0, -3, 0, 14, -14], [0, 7, -14, 0, 7, 28, -4, 4], [-28, -10, 0, 24, 10, 0, 2, 2], [0, 9, -26, 0, 9, -28, 0, 0], [0, 2, 0, 0, 2, 0, 10, -10], [0, 8, 2, 0, 8, 28, -10, 10], [14, -8, 0, -16, 8, 0, 8, 8], [32, 3, 0, 16, -3, 0, 1, 1], [-62, -1, 0, -4, 1, 0, 5, 5], [0, -5, 31, 0, -5, 12, -2, 2], [-20, 10, 0, 28, -10, 0, -2, -2], [0, 1, 5, 0, 1, -36, -6, 6], [-22, 4, 0, 24, -4, 0, -5, -5], [0, 5, 6, 0, 5, -20, 15, -15], [18, -13, 0, -14, 13, 0, -5, -5], [0, -2, 18, 0, -2, -16, -8, 8], [0, -11, 14, 0, -11, 28, -5, 5], [-28, -9, 0, 7, 9, 0, 20, 20], [-10, -10, 0, 0, 10, 0, 11, 11], [8, -2, 0, -5, 2, 0, 13, 13], [0, -2, 28, 0, -2, -12, 6, -6], [0, 4, -24, 0, 4, -38, -4, 4], [-2, -11, 0, 0, 11, 0, -1, -1], [0, 11, -29, 0, 11, -16, 2, -2], [44, 3, 0, 16, -3, 0, -6, -6], [-44, 1, 0, 5, -1, 0, 8, 8], [0, -12, 2, 0, -12, 0, 1, -1], [-8, 2, 0, -12, -2, 0, -10, -10], [0, -4, 8, 0, -4, -12, 12, -12], [0, 3, -12, 0, 3, -28, 8, -8], [0, -8, 12, 0, -8, -34, -12, 12], [8, 8, 0, 12, -8, 0, 0, 0]];
    aps := ConvertToHeckeField(raw_aps);
    chi := MakeCharacter_1470_g_Hecke(Universe(aps));
    return ExtendMultiplicatively(weight, aps, chi);
end function;


// To make the newform (type ModFrm), type "MakeNewformModFrm_1470_2_g_k();".
// This may take a long time!  To see verbose output, uncomment the SetVerbose lines below.
// The precision argument determines an initial guess on how many Fourier coefficients to use.
// This guess is increased enough to uniquely determine the newform.
function MakeNewformModFrm_1470_2_g_k(:prec:=8)
    chi := MakeCharacter_1470_g();
    f_vec := qexpCoeffs();
    Kf := Universe(f_vec);
    // SetVerbose("ModularForms", true);
    // SetVerbose("ModularSymbols", true);
    S := CuspidalSubspace(ModularForms(chi, 2));
    S := BaseChange(S, Kf);
    maxprec := NextPrime(1999) - 1;
    while true do
        trunc_vec := Vector(Kf, [0] cat [f_vec[i]: i in [1..prec]]);
        B := Basis(S, prec + 1);
        S_basismat := Matrix([AbsEltseq(g): g in B]);
        if Rank(S_basismat) eq Min(NumberOfRows(S_basismat), NumberOfColumns(S_basismat)) then
            S_basismat := ChangeRing(S_basismat,Kf);
            f_lincom := Solution(S_basismat,trunc_vec);
            f := &+[f_lincom[i]*Basis(S)[i] : i in [1..#Basis(S)]];
            return f;
        end if;
        error if prec eq maxprec, "Unable to distinguish newform within newspace";
        prec := Min(Ceiling(1.25 * prec), maxprec);
    end while;
end function;


// To make the Hecke irreducible modular symbols subspace (type ModSym)
// containing the newform, type "MakeNewformModSym_1470_2_g_k();".
// This may take a long time!  To see verbose output, uncomment the SetVerbose line below.
// The default sign is -1.  You can change this with the optional parameter "sign".
function MakeNewformModSym_1470_2_g_k( : sign := -1)
    R<x> := PolynomialRing(Rationals());
    chi := MakeCharacter_1470_g();
    // SetVerbose("ModularSymbols", true);
    Snew := NewSubspace(CuspidalSubspace(ModularSymbols(chi,2,sign)));
    Vf := Kernel([<11,R![32, -16, -18, 0, 1]>,<17,R![15376, 0, 8000, 0, 1336, 0, 80, 0, 1]>,<19,R![-448, -224, 12, 12, 1]>],Snew);
    return Vf;
end function;