Subject: Implicit: Taylor, Poiseux and Newton's diagram
From: Robert Dodier
Date: Fri, 1 Jun 2012 15:44:03 +0000 (UTC)
On 2012-06-01, Oliver Kullmann <O.Kullmann at swansea.ac.uk> wrote:
> Just a comment: I find the Maxima-usage of the notion of "identity" rather
> misleading, since in mathematical logic or other related areas, like
> term rewriting, "identity" just means identity, namely the terms are identical.
> So 1+1 is not identical to 2, not is 1+2 identical to 2+1.
Well, I think this is the same sense I meant, namely a is identical to b
iff they are the same atoms, or composites with the same parts and same
organization. But as RJF points out, simplification is applied, so by
the time "=" is assessed, its arguments might have changed.
> 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? It seems the evaluation
> (rewriting) of 1+1 to 2 is hard to avoid?
You could, with some simple programming, implement your own top-level
read-eval-print loop, which would act the way you want. Maybe just
simp:false is enough. I do see the value in controlling simplification
so if you care to explain what behavior you want, I would be interested
to see if we can figure it out.
best
Robert Dodier