On Mon, 2007-04-16 at 18:43 +0000, Wolfgang Lindner wrote:
> My students will (fequently) have to calculate function values,
> function tables etc.
> So - as far as I know - I should have to write
>
> (%i4) subst(x=4, f) /* instead of f(4) */
>
> if f is an term. Or is there an better possibility?
> If there would be an 'term evaluator' like
>
> (%i4') f | x=4 /* term f evaluated for x =4 */
>
> one would have a simpler and shorter 'functionlike' notation.
you can simply use:
(%i4'') f, x=4;
my students get used very quickly to that notation as a synonym for
f(x=4).
And for the derivatives:
fp: diff(f,x)
fpp: diff(fp,x)
...
finally, for the composed functions f^n(x),
f2: ev(f, x=f)
f3: ev(f2, x=f)
...
there are more places where Maxima now accepts functions instead of
expressions. There are still some problems as the one you pointed out
in solving equations. Hopefully, in future versions those problems
will be eliminated and we'll be able to use functions instead of
expressions.
Regards,
Jaime Villate