On Thu, 15 Oct 2009, Robert Dodier wrote:
< On Sat, Oct 10, 2009 at 2:55 AM, Leo Butler <l.butler at ed.ac.uk> wrote:
<
< > < > (%o6) if k-1 < 0 then integrate(%e^(%i*k*x)*sin(x)/x,x,minf,inf) elseif
< > < > equal(k-1,0) then %pi else 0
< > < >
< > < > The answer shows that when k-1<0 Maxima can't do the integration.
<
< > This shows a weakness in the noninteractive code. If you walk through
< > the cases that 'integrate' throws up, you will see that it does
< > correctly identify all the various conditions on k. The noninteractive
< > result you show is not following the various cases that are thrown up.
<
< Well, noninteractive only tries to construct one level of if-then-else.
< Often enough trying to follow up on the alternatives leads you
< down the rabbit hole. (I wrote it to continue trying to resolve
< each alternative, and it's easy to find examples for which that
< leads to endless looping or other problems.)
<
< Sometimes it's obvious that trying just one more time would yield
< a useful result. Dunno how to detect that automatically.
< I haven't looked at the present example but maybe it is one of
< those that could benefit from trying just a little harder.
<
< If someone would please file a bug report about it and assign it
< to me, that would be very helpful. Thanks for your interest in noninteractive.
Robert, I did file a bug report on it, but left it unassigned.
Leo
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