Negligible terms in polynomials



On Saturday 10 January 2009 15:46:23 Alexey Beshenov wrote:
> On Saturday 10 January 2009 15:35 you wrote:
> > Sorry but I have another problem... I'm trying to use your
> > freeof_var with the function  tou suggested me to make some terms
> > negligible in polynomials, here is a little example with a
> > matrix:
>
> I just changed the order of arguments to make freeof_var
> definition shorter. So you should replace freeof(A,e) by
> freeof_var(e,A), etc.
>
> Redefine freeof_var in an appropriate way, if needed.

freeof_var ([xe]) := block ([v, x, e],
  if xe=[] then return(true),
  block ([ex : reverse(xe)].
    e : first (ex),
    x : rest (ex)
  ),
  v : listofvars (e),
  while true do (
    if x=[] then
      return (true)
    elseif member(first(x),v) then
      return (false)
    else
      x : rest(x)
  )
)$


freeof (x, x[1]+y) => false
freeof_var (x, x[1]+y) => true

map (lambda([e], if freeof(A,e) or freeof(I,e) then e else
limit(e, A, inf)), u) => matrix([M/I],[M/I],[F/A])

map (lambda([e], if freeof_var(A,e) or freeof_var(I,e) then e else 
limit(e, A, inf)), u) => matrix([M/I],[M/I],[F/A])

-- 
Setting Orange, Chaos 10 YOLD 3175
Alexey Beshenov  http://beshenov.ru/