Linearity of sum



On 10/17/2010 03:48 PM, Stavros Macrakis wrote:
> Declaring f linear in Maxima is not just an assertion of a
> mathematical property -- it means that f(a+b) automatically simplifies
> to f(a)+f(b).  In many cases users want more control than this.
>
> In the case of sum in particular, *infinite* sum is not linear in
> general and Maxima can't know whether sum(...,n) is going to have
> n->inf later in a calculation.

Thanks for this explanation, it makes sense. as for the issue about 
integration of sums causing problems, where Maxima knows how to 
integrate the individual terms but not how to integrate the sum. What is 
the best way to deal with that? This arises sometimes both with 'sum as 
well as with small sums made up of + expressions. I don't have an 
example ready to hand unfortunately.