Order of integration



One way to start may be to replace "integrate"  with some other name, so
that maxima won't actually try to integrate anything.
Try  subst(ii,'integrate,%)  or some such thing.

RJF

-----Original Message-----
From: maxima-bounces at math.utexas.edu [mailto:maxima-bounces at math.utexas.edu]
On Behalf Of Rupert Swarbrick
Sent: Thursday, August 23, 2007 2:10 PM
To: Maxima Mailing list
Subject: Re: [Maxima] Order of integration

On Thu, 23 Aug 2007 09:54:59 -0700
"Richard Fateman" <fateman at cs.berkeley.edu> wrote:
> In my
> case, the regions of integration are triangular and rectangular.
> 
> This sounds easy.   I don't know if changevar() will help you. Check
> it out. RJF

Thanks for the reply. I'm not sure that changevar() will do it - it
seems to only be able to do "one variable at once" - what could you
give it for "f(x,y)" as in the docs?

I might have a stab at writing a function myself to try and do it for
rectangular regions, say. One problem, though: Maxima (intelligently)
takes terms that are constant inside the inner integral out into the
outer integral, so

integrate( integrate( f(x,y)*g(x), y, a,b ), x,c,d )

becomes

integrate( g(x)*integrate( f(x,y), y, a,b ), x,c,d )

Is there a way to reverse this process?

Rupert