monomialOrderDecodeToActualExponents()

void monomialOrderDecodeToActualExponents	(	const MonomialOrder *	mo,
		const_monomial	a,
		exponents_t	b )

Definition at line 548 of file imonorder.cpp.

{
  if (mo == nullptr) return;
  int *tmpexp = static_cast<int *>(alloca((mo->nvars + 1) * sizeof(int)));
  int i, j, nvars;
  deg_t *degs = mo->degs;
  deg_t *d;
  struct mo_block *b = mo->blocks;
  int nblocks = mo->nblocks;
  int *e = expon;
  const int *p = psums;
  for (i = nblocks; i > 0; --i, b++) switch (b->typ)
      {
        case MO_LEX:
        case MO_LAURENT:
          nvars = b->nvars;
          p = psums + b->first_slot;
          e = expon + b->first_exp;
          for (j = 0; j < nvars; j++) *e++ = *p++;
          break;
        case MO_REVLEX:
        case MO_LAURENT_REVLEX:
          nvars = b->nvars;
          p = psums + b->first_slot;
          e = expon + b->first_exp;
          for (j = 0; j < nvars; j++) *e++ = safe::minus(*p++);
          break;
        case MO_GREVLEX:
          nvars = b->nvars;
          p = psums + b->first_slot + nvars - 1;
          e = expon + b->first_exp;
          *e++ = *p--;
          for (j = nvars - 1; j >= 1; --j, --p) *e++ = safe::sub(*p, p[1]);
          break;
        case MO_GREVLEX_WTS:
          nvars = b->nvars;
          d = degs + b->first_exp;
          p = psums + b->first_slot + nvars - 1;
          e = expon + b->first_exp;
          *e++ = *p-- / *d++;
          for (j = nvars - 1; j >= 1; --j, --p)
            *e++ = safe::sub(*p, p[1]) / *d++;
          break;
        case MO_GREVLEX4:
          nvars = b->nvars;
          MO_unpack4(nvars, psums + b->first_slot, tmpexp);
          p = tmpexp + nvars - 1;
          e = expon + b->first_exp;
          *e++ = *p--;
          for (j = nvars - 1; j >= 1; --j, --p) *e++ = safe::sub(*p, p[1]);
          break;
        case MO_GREVLEX4_WTS:
          nvars = b->nvars;
          d = degs + b->first_exp;
          MO_unpack4(nvars, psums + b->first_slot, tmpexp);
          p = tmpexp + nvars - 1;
          e = expon + b->first_exp;
          *e++ = *p-- / *d++;
          for (j = nvars - 1; j >= 1; --j, --p)
            *e++ = safe::sub(*p, p[1]) / *d++;
          break;
        case MO_GREVLEX2:
          nvars = b->nvars;
          MO_unpack2(nvars, psums + b->first_slot, tmpexp);
          p = tmpexp + nvars - 1;
          e = expon + b->first_exp;
          *e++ = *p--;
          for (j = nvars - 1; j >= 1; --j, --p) *e++ = safe::sub(*p, p[1]);
          break;
        case MO_GREVLEX2_WTS:
          nvars = b->nvars;
          d = degs + b->first_exp;
          MO_unpack2(nvars, psums + b->first_slot, tmpexp);
          p = tmpexp + nvars - 1;
          e = expon + b->first_exp;
          *e++ = *p-- / *d++;
          for (j = nvars - 1; j >= 1; --j, --p)
            *e++ = safe::sub(*p, p[1]) / *d++;
          break;
        case MO_LEX4:
          nvars = b->nvars;
          e = expon + b->first_exp;
          MO_unpack4(nvars, psums + b->first_slot, e);
          break;
        case MO_LEX2:
          nvars = b->nvars;
          e = expon + b->first_exp;
          MO_unpack2(nvars, psums + b->first_slot, e);
          break;
        case MO_WEIGHTS:
          break;
        case MO_POSITION_UP:
        case MO_POSITION_DOWN:
          /* should not occur, but do nothing in any case */
          break;
        case MO_NC_LEX:
          /* nothing to do here */
          break;
      }
}

References mo_block::first_exp, mo_block::first_slot, safe::minus(), MO_GREVLEX, MO_GREVLEX2, MO_GREVLEX2_WTS, MO_GREVLEX4, MO_GREVLEX4_WTS, MO_GREVLEX_WTS, MO_LAURENT, MO_LAURENT_REVLEX, MO_LEX, MO_LEX2, MO_LEX4, MO_NC_LEX, MO_POSITION_DOWN, MO_POSITION_UP, MO_REVLEX, MO_unpack2(), MO_unpack4(), MO_WEIGHTS, mo_block::nvars, p, safe::sub(), and mo_block::typ.

Referenced by Monoid::to_expvector().