depends(t,x) declares a dependency of the *variable* t (not the function t)
on another variable.
It is confusing, I agree, but that is traditional mathematical notation for
you....
-s
2009/6/11 Martin Sch?necker <ms_usenet at gmx.de>
> Maybe I'm missing something in the following simple example:
>
> x depends on x, a and t do not depend on z. I would have expected
> diff(a(t), z) to evaluate to zero, as well - at the latest in line 5.
>
> Is this a bug?
>
> Martin
>
>
> wxMaxima 0.8.2 http://wxmaxima.sourceforge.net
> Maxima 5.18.1 http://maxima.sourceforge.net
> Using Lisp GNU Common Lisp (GCL) GCL 2.6.8 (aka GCL)
> Distributed under the GNU Public License. See the file COPYING.
> Dedicated to the memory of William Schelter.
> The function bug_report() provides bug reporting information.
> (%i7) kill(all);
> (%o0) done
> (%i1) depends(t, x);
> (%o1) [t(x)]
> (%i2) diff(t, z);
> diff(a, z);
> (%o2) 0
> (%o3) 0
> (%i4) diff(a(t), z);
> ev(%, diff);
> (%o4) 'diff(a(t),z,1)
> (%o5) 'diff(a(t),z,1)
> (%i6) dependencies;
> (%o6) [t(x)]
>
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