`p_terms'
---------

p_terms(POLY,VLIST,ORDER)
     :: Monomials appearing in the given polynomial is collected into a
     list.

RETURN
     list

POLY
     polynomial

VLIST
     list

ORDER
     number, list or matrix

   * Defined in the package `gr'.

   * This returns a list which contains all non-zero monomials in the
     given polynomial.  The monomials are ordered according to the
     current type of term ordering and VLIST.

   * Since polynomials in a Groebner base often have very large
     coefficients, examining a polynomial as it is may sometimes be
     difficult to perform.  For such a case, this function enables to
     examine which term is really exists.

     [233] G=gr(katsura(5),[u5,u4,u3,u2,u1,u0],2)$
     [234] p_terms(G[0],[u5,u4,u3,u2,u1,u0],2);
     [u5,u0^31,u0^30,u0^29,u0^28,u0^27,u0^26,u0^25,u0^24,u0^23,u0^22,
     u0^21,u0^20,u0^19,u0^18,u0^17,u0^16,u0^15,u0^14,u0^13,u0^12,u0^11,
     u0^10,u0^9,u0^8,u0^7,u0^6,u0^5,u0^4,u0^3,u0^2,u0,1]

