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// mwprocs.h: definition of class mw for Mordell-Weil basis
//////////////////////////////////////////////////////////////////////////
//
// Copyright 1990-2012 John Cremona
//
// This file is part of the eclib package.
//
// eclib is free software; you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2 of the License, or (at your
// option) any later version.
//
// eclib is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License
// along with eclib; if not, write to the Free Software Foundation,
// Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
//
//////////////////////////////////////////////////////////////////////////
// allow for multiple includes
#ifndef _ECLIB_MWPROCS_
#define _ECLIB_MWPROCS_
#include "saturate.h"
#include "sieve_search.h"
// global to this file -- size of height_pairing matrix, equal
// to maximum rank of any curve likely to study
const int MAXRANK = 30;
const int MAXSATPRIME = 20; // default saturation limit
class mw : public point_processor {
private:
Curvedata *E;
vector<Point> basis;
int rank, maxrank;
bigfloat *height_pairs;
bigfloat reg;
int verbose, process_points;
bigfloat& mat_entry(int i, int j);
bigint a1,a2,a3,a4,a6;
int iso;
saturator satsieve;
public:
mw(Curvedata*, int verb=0, int pp=1, int maxr=999);
~mw();
// processing of new points, with saturation at primes up to sat
// (default MAXSATPRIME, none if sat==0)
int process(const bigint& x, const bigint& y, const bigint& z);
int process(const bigint& x, const bigint& y, const bigint& z, int sat);
// as returned by ms's sieve; the point is (x/z,y/z^(3/2)) and z is square
int process(const Point& P, int sat=MAXSATPRIME);
int process(const vector<Point>& Plist, int sat=MAXSATPRIME);
// saturate the current basis:
int saturate(long& index, vector<long>& unsat, long sat_bd=-1, long sat_low_bd=0);
void search(bigfloat h_lim, int moduli_option=0, int verb=0);
void search_range(bigfloat xmin, bigfloat xmax, bigfloat h_lim,
int moduli_option=2, int verb=0);
bigfloat regulator(void) {return reg;}
vector<Point> getbasis() {vector<Point> b(basis.begin(),basis.begin()+rank); return b;}
int getrank() {return rank;}
};
inline bigfloat& mw::mat_entry(int i, int j)
{
return *(height_pairs + (i*MAXRANK) + j);
}
class sieve {
private:
Curvedata *E;
bigint a1,a2,a3,a4,a6;
bigint d1,d2,d3,d4,d6,c2,c3,c4,c6;
long a,c;
mw * mwbasis;
int verbose, posdisc, firstnl;
bigfloat xmin,x1,x2,x3;
int num_aux;
long* auxs;
int** xgood_mod_aux;
int** x1good_mod_aux;
int** squares;
long* amod;
long *modhits;
long npoints, ascore, amodc, alim, clim0, clim1, clim2, clim;
int* cflag; int use_cflag;
void a_search(const long& amin, const long& amax);
void a_simple_search(const long& amin, const long& amax);
public:
sieve(void) {;}
sieve(Curvedata * EE, mw* mwb, int moduli_option, int verb=0);
~sieve();
void search(bigfloat h_lim);
void search_range(bigfloat xmin, bigfloat xmax, bigfloat h_lim);
void stats(); // report sieving statistics
};
int order_real_roots(vector<double>& bnd, vector<bigcomplex> roots);
//checks (and returns) how many roots are actually real, and puts those in
//bnd, in increasing order, by calling set_the_bound
int set_the_bounds(vector<double>& bnd, bigfloat x0, bigfloat x1, bigfloat x2);
//This transforms (if possible) x0, x1 and x1 into double; the search
//should be made on [x0,x1]U[x2,infty] so if x1 or x2 overflows, the search
//is on [x0,infty]. The function returns 3 in the first case, 1 in the second.
//If x0 overflows, it returns 0. A warning is printed out.
#endif
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