On 26-09-2013 02:10, Stavros Macrakis wrote:
>
> Why infeval?
>
Because that's what Redfern, Chandler and Fell propose in their book and
I have not been able to find an alternative:
(%i2) b2:4$
(%i3) ev(concat(b,2));
(%o3) b2
(%i4) ev(ev(concat (b,2)));
(%o4) b2
(%i5) ev(concat (b,2),infeval);
(%o5) 4
do you know another way to get the value 4 without using ''(...) ?
Jaime
>
> -s
>
> On Sep 25, 2013 12:47 PM, "Jaime Villate" <villate at fe.up.pt
> <mailto:villate at fe.up.pt>> wrote:
>
> I think that the result Christian was expecting is what you get from:
>
> for j:1 thru 2 do (
> concat (b,j) :: 10*j,
> print (ev (concat (b,j), infeval)));
>
> There is a very nice old book: Darren Redfern, Edgar Chandler and
> Richard N. Fell, Macsyma ODE Lab Book, 1998, where the authors use
> concat() and ''(...) very intensely.
> They do switch from ''(concat(...)) to ev(concat(...),infeval)
> inside for loops.
>
> I do agree that concat(...) and ''(...) should be avoided in favor
> of other better ways to do the same.
> Regards,
> Jaime
>