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/*!
@class MinimalPrimes
@abstract (description)
@discussion (description)
*/
// (c) 1994-2005 Michael E. Stillman
#ifndef _monideal_minprimes_h_
#define _monideal_minprimes_h_
#include "monideal.hpp"
#include "queue.hpp"
class MinimalPrimes
// A class which enables one to compute the codimension and
// associated primes of minimal codimension, of a monomial ideal.
{
enum { do_codim, do_primes } state;
int min_codim;
int nvars;
MonomialIdeal *mi; // A radical monomial ideal
MonomialIdeal *primes;
queue<Bag *> Q; // Each monomial corresponds to a potential prime monomial
// ideal: a monomial is the product of the gens of
// the prime ideal.
int codim_limit; // only consider monomial primes of codim <= this number.
int minprime_limit; // -1 means find all. >= 1 means stop after that number
int n_minprimes; // number found so far, during associated_primes computation
int **exps;
int depth_limit; // -codim_limit-1
int *exp;
int *exp2;
int *monoms;
void alg1_grab_prime(int depth);
void alg1_min_prime_generator(int *which, int depth);
void ass_prime_generator(Nmi_node *p, int codim);
public:
MinimalPrimes(const MonomialIdeal *const &mi);
~MinimalPrimes();
int codimension();
MonomialIdeal *associated_primes(int count);
MonomialIdeal *alg1_min_primes(int maxcodim, int count);
MonomialIdeal *min_primes(int maxcodim, int count);
// maxcodim == nvars means get all of them
// count == -1 means no limit
// return value: A monomial ideal where each
// monomial prime ideal is represented as a
// monomial: the product of the generators.
// NOTE: this is the complement of the gens from
// max_indep_sets
MonomialIdeal *max_indep_sets(int count);
public:
// Static routines:
static int codimension(const MonomialIdeal *I);
static MonomialIdeal *min_primes(const MonomialIdeal *I,
int maxcodim,
int count);
static MonomialIdeal *max_indep_sets(const MonomialIdeal *I, int count);
};
#endif
// Local Variables:
// compile-command: "make -C $M2BUILDDIR/Macaulay2/e "
// indent-tabs-mode: nil
// End:
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