wrong symbolic sum



-----maxima-bounces at math.utexas.edu wrote: -----

>Be?assured?that?the?solution?you?(Robert)??propose?(making?the?summand
>evaluated?normally)?was?tried?first?and
found?inadequate.?But?maybe?expectations?change.

Was it inadequate because users didn't want to learn when to quote? Look at
what
happens now:

Yippee! Magically what the user wants:

 (%i1) sum(concat(%a,k) * x^k,k,0,3);
 (%o1) %a3*x^3+%a2*x^2+%a1*x+%a0

Yikes! A known bug:

 (%i2) sum(concat(%a,k) * x^k,k,0,n);
 (%o2) %ag34036*sum(x^k,k,0,n)

The cure is to quote:

 (%i3) sum('(concat(%a,k)) * x^k,k,0,n);
 (%o3) sum(concat(%a,k)*x^k,k,0,n)

Some times the summand *still* needs to be quoted. There are lots of other
issues too, but I can't think of them right now.

Barton