Function k_SplitFrame

libpolys/polys/shiftop.cc:600–621

splits a frame (e.g. x(1)*y(5)) m1 into m1 and m2 (e.g. m1=x(1) and m2=y(1)) at is the number of the block to split at, starting at 1

// splits a frame (e.g. x(1)*y(5)) m1 into m1 and m2 (e.g. m1=x(1) and m2=y(1))
// at is the number of the block to split at, starting at 1
void k_SplitFrame(poly &m1, poly &m2, int at, const ring r)
{
  assume(at >= 1);
  assume(at <= r->N/r->isLPring);
  int lV = r->isLPring;
  int split = (lV * (at - 1));

  m2 = p_GetExp_k_n(m1, 1, split, r);
  p_SetComp(m2, 0, r); // important, otherwise both m1 and m2 have a component set, this leads to problems later
  p_Setm(m2, r); // p_mLPunshift also implicitly calls p_Setm(), but just for the case this changes in future.
  p_mLPunshift(m2, r);

  m1 = p_Head0(m1, r);
  for(int i = split + 1; i <= r->N; i++)
  {
    p_SetExp(m1, i, 0, r);
  }
  p_Setm(m1, r);

  assume(p_FirstVblock(m1,r) <= 1);
  assume(p_FirstVblock(m2,r) <= 1);
}

BOOLEAN _p_mLPNCGenValid(poly p, const ring r)
{