Subject: Implicit: Taylor, Poiseux and Newton's diagram
From: Richard Fateman
Date: Fri, 01 Jun 2012 06:52:08 -0700
On 6/1/2012 12:29 AM, Oliver Kullmann wrote:
...
> By the way, how would one actually check in Maxima for identity, so
> that "1+1" is only identical to "1+1" and nothing else?
Routinely, Maxima does not deal with unsimplified objects. A working
definition of unsimplified:
any expression that would be changed by the simplifier program (simplifya).
Therefore" is (A=B) " really tests to see if simplify(A) and
simplify(B) are the same expression trees, where atoms in
corresponding places must be lisp equal.
If you wanted to deal with expressions like 1+1, you could try simp:off
in Maxima, in which case you will find many programs
don't work as expected, or you could just not use Maxima and write in
Lisp. This latter choice is not meant sarcastically.
If you turn off the simplifier in Maxima, you disable most of the
system, anyway.
> It seems the evaluation (rewriting) of 1+1 to 2 is hard to avoid?
For what it is worth, this is not being done by evaluation, but by the
simplifier. I'm not sure that using the
term "rewriting" is incorrect, but it may be misleading. If you mean by
r := f(s) the same as "rewrite s as r using rule f" then I
guess they are the same.
RJF
> Oliver P.S. In our application we use nearly only "=" in tests, since
> we are typically handling basic combinatorial objects, lists of sets
> of lists and the like, with simple terms in it, and then "=" does the
> job, and is likely faster: if {1+1,3-2}={1,2} then 0 else 1; 0
> _______________________________________________ Maxima mailing list
> Maxima at math.utexas.edu http://www.math.utexas.edu/mailman/listinfo/maxima