On Mon, Mar 24, 2008 at 9:45 AM, Raymond Toy (RT/EUS)
<raymond.toy at ericsson.com> wrote:
> While playing with donlp2, I noticed that maxima orders vector variables
> in "reverse" order. For example,
>
> sum(x[k],k,1,5) -> x[5]+x[4]+x[3]+x[2]+x[1].
>
> While I usually just accept whatever order maxima wants to display
> variables, this particular example seems wrong. There's a natural
> ordering and it's by the index of the variable.
>
> Any reason why it should be in reverse order? Any objections to
> changing it for this case? (I don't know if that's really possible or
> not. I haven't looked.)
The terms x[1], x[2], ... are stored in order of increasing index.
Whether they are displayed that way or reversed is controlled
by the global variable powerdisp. When powerdisp=true the terms
are displayed in order of increasing index.
I'm not opposed to changing the default value of powerdisp to true.
Aside from changing powerdisp, we could also change GREAT
(the function which implements Maxima's idea of canonical
ordering). Changing GREAT could have rippling effects, though.
FWIW
Robert Dodier