Rich,
Automatic taking of limits is not always the answer for many people.
Personnally I would like this feature
(%i1) solve (sin(x-y)/(x-y)=0,x);
(%o1) []
since I think a "solution" that makes the demominator zero is never "right".
Rich
----- Original Message -----
From: "Richard Fateman" <fateman at cs.berkeley.edu>
To: "'Richard Hennessy'" <rvh2007 at comcast.net>
Cc: <maxima at math.utexas.edu>
Sent: Wednesday, September 10, 2008 11:04 AM
Subject: RE: [Maxima] integrate returns undefined
> Your saying that something is not a bug does not mean everyone will agree
> with you.
> Or even that it will result in non-buggy results. Many "bugs" reported on
> sci.math.symbolic
> by one writer as bugs in "integrate" in Maple, are bugs in
> simplification,
> sometimes
> just like this "obvious" but sometimes wrong feature.
>
> In particular, you may not need reminding about a=0 in this case, but what
> about
> in other cases, where Maxima just goes ahead without you... e.g.
> solve (sin(x-y)/(x-y)=0,x)
>
> returns x=y;
> but this is not a solution, which can be seen either by direct
> substitution
> or
> taking a limit.
>
> RJF
>
>
>
>
>
>
>
>> -----Original Message-----
>> From: Richard Hennessy [mailto:rvh2007 at comcast.net]
>> Sent: Wednesday, September 10, 2008 7:26 AM
>> To: fateman at EECS.Berkeley.EDU; 'John Pye'; maxima at math.utexas.edu
>> Cc: 'Edwin Woollett'
>> Subject: Re: [Maxima] integrate returns undefined
>>
>> This is not a bug, this simplifies to 1
>>
>> a/a -> 1
>>
>> with no assumptions made. I have noticed that in general
>> radcan(expr1/expr1) simplifies to 1 and Maxima never says
>> except when expr1
>> = 0. Which I find useful since I know about the possibility
>> that expr1
>> could be zero but I don't really need to be reminded of this case. I
>> definitely would not want to be asked is expr1 = zero all the
>> sime when
>> cancelling terms. That would be annoying.
>>
>> Rich
>>
>>
>> ----- Original Message -----
>> From: "Richard Fateman" <fateman at cs.berkeley.edu>
>> To: "'John Pye'" <john.pye at anu.edu.au>; <maxima at math.utexas.edu>
>> Cc: "'Edwin Woollett'" <woollett at charter.net>
>> Sent: Tuesday, September 09, 2008 11:56 PM
>> Subject: Re: [Maxima] integrate returns undefined
>>
>>
>> > Not so clear a bug.
>> > (n-m)/(n-m) simplifies to 1.
>> > But if you know n=m, then you have 0/0. So is it a bug if
>> (n-m)/(n-m) -->
>> > 1?
>> >
>> > Answer: maybe. But not clear :)
>> >
>> > RJF
>> >
>> >
>> >> -----Original Message-----
>> >> From: maxima-bounces at math.utexas.edu
>> >> [mailto:maxima-bounces at math.utexas.edu] On Behalf Of John Pye
>> >> Sent: Tuesday, September 09, 2008 6:47 PM
>> >> To: maxima at math.utexas.edu
>> >> Cc: Edwin Woollett
>> >> Subject: Re: [Maxima] integrate returns undefined
>> >>
>> >> I can confirm that behaviour; it looks like a clear bug to me.
>> >>
>> >> Cheers
>> >> JP
>> >>
>> >> Edwin Woollett wrote:
>> >> > integrate(..) returns undefined when it
>> >> > should know the answer.
>> >> >
>> >> > (%i1) declare( [ m, n ], integer )$
>> >> > (%i2) assume ( m > 0, n > 0 )$
>> >> > (%i3) integrate( cos(m*x)^2, x, 0, 2*%pi );
>> >> > (%o3) %pi
>> >> > (%i4) integrate( cos(m*x)*cos(n*x), x, 0, 2*%pi );
>> >> > Is n - m positive, negative, or zero?
>> >> >
>> >> > zero;
>> >> > (%o4) undefined
>> >> >
>> >> > Is this a known bug?
>> >>
>> >> _______________________________________________
>> >> Maxima mailing list
>> >> Maxima at math.utexas.edu
>> >> http://www.math.utexas.edu/mailman/listinfo/maxima
>> >>
>> >
>> > _______________________________________________
>> > Maxima mailing list
>> > Maxima at math.utexas.edu
>> > http://www.math.utexas.edu/mailman/listinfo/maxima
>>
>>
>