二元函数多项式排序问题

Question

我想对二元函数按照各项幂指数之和有大到小排序，可是效果不如人意，请大家指点一下

poly = -10 x^5 y^4 z^2 + 7 x^2 y^5 z^3 - 10 x^2 y z^5 - 7 x y^5 z^4 + 
  6 x y^4 z^3 + 6 x y^3 z^3 + 3 x y^2 z + y^4 z - 7 y^2 z + 2 z^5
  StringJoin[
 Riffle[ToString[#, TraditionalForm] & /@ 
   MonomialList[poly, {x, y, z}, {{1, 1, 1}, {1, 1, 1}, {1, 1, 1}}], 
  "+"]]

 

Answer 1

OrderedForm = HoldForm[+##] & @@ MonomialList[#][[
     Ordering[Total[#] & @@@ CoefficientRules[#], All, GreaterEqual]]] &;

poly//OrderedForm

来源：http://mathematica.stackexchange.com/questions/33130/why-does-mathematica-order-polynomial-forms-in-reverse-from-traditional-order/33133#33133