confusing solution set of exp-equation



Dear Richard,
 thank you very much, both hints are very welcome, demonstrating nice and clever use of
Maxima's syntactic abilities. I like it.
And I see that I have to learn much more :)
 HTH
Wolfgang

  "Richard Fateman" <fateman at cs.berkeley.edu> schrieb: 
You can often do this:

fun(x):=''f

fun(4)


instead of   subst(x=4,f)

Maybe that will solve your problem.

It is possible to set derivabbrev:true

to change the output of derivatives to look like subscripts.
If you wish, you might be able to use

df[n]:= diff(f,x,n)

and then a DE might look like    df[2]-a*f=0

RJF


Wolfgang Lindner wrote:
"Stavros Macrakis" <macrakis at alum.mit.edu> schrieb: On 4/15/07, Wolfgang Lindner
<LindnerW at t-online.de> wrote:
  (%i1) f(x):=exp(x)-1/4*x*exp(x);(%i2) solve(f(x)=0,x);(%o2) [x=4,%e^x=0](%i3)
diff(f(x),x) ;  /* f prime */ ...AFAIK it is not possible to abbrevitae  diff(f(x),x) 
with  f'(x).I use fp(x) to name 'f prime' etc. Is there any symbol left (backquote?) to
name f'(x) and causing no problems later?What is your recommended work around?
      
  As a general rule, Maxima does a much better job with mathematical *expressions*
thanwith mathematical *functions* with names (like f). So the natural way to handle this
sort of thing in Maxima isf: exp(x)-1/4*x*exp(x);solve(f,x)$solve(diff(f,x),x)etc.>>
    Thank you for your interesting hints on Maxima's capabilities. In Germany we have
a'didactical tradition in math' to perfer *functions* (at least since Felix Klein),
notterms - but using CAS the situation seems be on other one.Following your advice will
there be an 'uncomfortable term evaluation'?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.So I have to decide:
function - maybe no good job
                     term     - no usual evaluation a la f(x)
  HTH WolfgangLeichlingen/Germany_______________________________________________Maxima
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