On 4/29/11, Litvinov Sergey <slitvinov at gmail.com> wrote:
> Why I cannot simplify this?
>
>
> I get
> taylor: unable to expand at a point specified in:
>
> This works
> sum(taylor( exp(-x*R[i]), x, 0, 1), i, 1, N);
>
>
> Maxima 5.21.1 using Lisp CLISP 2.49 (2010-07-07)
There's something missing from your original message
(and the subsequent ones didn't fix the problem).
I see something interesting here. It may or may not be
related to the problem you have observed.
taylor (exp (x), x, 0, 1);
=> /T/ 1 + x + . . .
:lisp $%
=> ((MRAT SIMP (((MEXPT SIMP) $%E $X) $X) (%e^x21874 X21875)
(($X ((1 . 1)) 0 NIL X21875 . 2)) TRUNC)
PS (X21875 . 2) ((1 . 1)) ((0 . 1) 1 . 1) ((1 . 1) 1 . 1))
foo (taylor (exp (x), x, 0, 1));
=> foo(x + 1)
:lisp $%
=> (($FOO SIMP) ((MPLUS SIMP) 1 $X))
The taylor-ness of the expression was apparently thrown away
when it was the argument of some other operator.
I don't know if that's by design or what.
best
Robert Dodier