pbc_poly.h

这是一个C的源代码

//requires
// * gmp.h
// * field.h
// * darray.h
#ifndef __PBC_POLY_H__
#define __PBC_POLY_H__

//implements R[x] for a given ring R
//also R[x]_{f(x)}
struct poly_field_data_s {
    field_ptr field;
    fieldmap mapbase; //map element from underlying field to constant term
};
typedef struct poly_field_data_s poly_field_data_t[1];
typedef struct poly_field_data_s *poly_field_data_ptr;

//TODO: having this structure is unnecessary? what else could be needed besides coeff?
struct poly_element_s {
    darray_t coeff;
};
typedef struct poly_element_s poly_element_t[1];
typedef struct poly_element_s *poly_element_ptr;

struct polymod_field_data_s {
    field_ptr field;
    fieldmap mapbase;
    int n; //degree of extension
    element_t poly; //polynomial of degree n
    element_t *xpwr; //holds x^n,...,x^{2n-2} mod poly
};
typedef struct polymod_field_data_s polymod_field_data_t[1];
typedef struct polymod_field_data_s *polymod_field_data_ptr;

static inline int poly_coeff_count(element_ptr e)
{
    return ((poly_element_ptr) e->data)->coeff->count;
}

static inline int poly_degree(element_ptr e)
{
    return poly_coeff_count(e) - 1;
}

static inline element_ptr poly_coeff(element_ptr e, int i)
{
    return (element_ptr) ((poly_element_ptr) e->data)->coeff->item[i];
}

void poly_alloc(element_ptr e, int n);
void poly_remove_leading_zeroes(element_ptr e);
void poly_set_coeff(element_ptr e, element_ptr a, int n);
void poly_setx(element_ptr f);
void poly_const_mul(element_ptr res, element_ptr a, element_ptr poly);
void poly_div(element_ptr quot, element_ptr rem,
	element_ptr a, element_ptr b);

void field_init_poly(field_ptr f, field_ptr base_field);
void field_init_polymod(field_ptr f, element_ptr poly);

void trial_divide(darray_ptr factor, darray_ptr mult, mpz_t n, mpz_ptr limit);

static inline field_ptr poly_base_field(element_t f)
{
    return ((poly_field_data_ptr) f->field->data)->field;
}

void poly_gcd(element_ptr d, element_ptr f, element_ptr g);
int poly_is_irred(element_ptr f);
void poly_invert(element_ptr res, element_ptr f, element_ptr m);
void poly_random_monic(element_ptr f, int deg);
void poly_make_monic(element_t f, element_t g);
void element_field_to_poly(element_t poly, element_t constant);

void element_polymod_to_poly(element_ptr f, element_ptr e);
void element_field_to_polymod(element_ptr f, element_ptr a);
void element_poly_to_polymod_truncate(element_ptr f, element_ptr e);
element_ptr polymod_coeff(element_ptr e, int i);

void polymod_const_mul(element_ptr res, element_ptr a, element_ptr e);
int polymod_field_degree(field_t f);
#endif //__PBC_POLY_H__