Just a word of caution with respect to simplify_full().
If your function involves floating point numbers, simplify_full() can
give an erroneous result (see bug #2604950 in Maxima or
http://groups.google.com/group/sage-devel/browse_thread/thread/5613095ef16c9ead/43a97f9690f5f8af?lnk=gst&q=simplify_full#43a97f9690f5f8af).
Also the following example shows a wrong result returned by
simplify_full() even without floats.
----------------------------------------------------------------------
| Sage Version 3.3, Release Date: 2009-02-21 |
| Type notebook() for the GUI, and license() for information. |
----------------------------------------------------------------------
sage: var('omgo zr ys cz')
(omgo, zr, ys, cz)
sage: omgo = (sqrt(-zr^2 + 2*ys*zr + (2*cz - zr)^2 - 2*ys*(2*cz - zr))
+ 2*zr- 2*cz)/(2*zr - 2*cz)
sage: omgo.simplify_full()
(I*sqrt(cz - ys)*sqrt(zr - cz) + zr - cz)/(zr - cz)
Now plucking in a few numbers for the variables shows that the results
before and after simplification are very different.
sage: omgo(cz=10,ys=5,zr=4).n()
0.0871290708247230
sage: omgo.simplify_full()(cz=10,ys=5,zr=4).n()
1.91287092917528
This is taken from the following thread:
http://groups.google.com/group/sage-support/browse_thread/thread/5d8ebc7250e1df69/a897d06b6fdfc021?lnk=gst&q=simplify_full()#a897d06b6fdfc021
My personal conclusion is to stay away from simplify_full() until I
know when to expect correct results from it.
Stan
On Jan 20, 10:56 am, Jason Grout <jason-s...@creativetrax.com> wrote:
> Tim Lahey wrote:
> > However, in my version of Sage (3.2), the functions simplify_full()
> > and simplify_trig() only seem to be defined on objects not as
> > general functions. Unless I'm missing something.
>
> I noticed that too. Does anyone object to making at least simplify_full
> a top-level function?
>
> Jason
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