Function id_DelMultiples

libpolys/polys/simpleideals.cc:295–326

ideal id = (id[i]), c any unit if id[i] = c*id[j] then id[j] is deleted for j > i

/// ideal id = (id[i]), c any unit
/// if id[i] = c*id[j] then id[j] is deleted for j > i
void id_DelMultiples(ideal id, const ring r)
{
  id_Test(id, r);

  int i, j;
  int k = IDELEMS(id)-1;
  for (i=k; i>=0; i--)
  {
    if (id->m[i]!=NULL)
    {
      for (j=k; j>i; j--)
      {
        if (id->m[j]!=NULL)
        {
          if (rField_is_Ring(r))
          {
            /* if id[j] = c*id[i] then delete id[j].
               In the below cases of a ground field, we
               check whether id[i] = c*id[j] and, if so,
               delete id[j] for historical reasons (so
               that previous output does not change) */
            if (p_ComparePolys(id->m[j], id->m[i],r)) p_Delete(&id->m[j],r);
          }
          else
          {
            if (p_ComparePolys(id->m[i], id->m[j],r)) p_Delete(&id->m[j],r);
          }
        }
      }
    }
  }
}

/// ideal id = (id[i])
/// if id[i] = id[j] then id[j] is deleted for j > i