Dear list,
I have a question about the interaction between limits (perhaps also
integrals?) and assumptions. See the floor(x) example in the
following session.
Maxima 5.19.1 http://maxima.sourceforge.netUsing Lisp SBCL
1.0.30Distributed under the GNU Public License. See the file
COPYING.Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%i1) assume(x<-2);
(%o1) [x < - 2]
(%i2) limit(floor(y),y,0);
(%o2) und
(%i3) limit(x^2,x,0);
(%o3) 0
(%i4) limit(floor(x),x,0);
(%o4) limit floor(x)
x -> 0
(%i5) limit(sin(x)/x,x,0);
(%o5) 1
(%i6) forget(x<-2);
(%o6) [x < - 2]
(%i7) limit(floor(x),x,0);
(%o7) und
In some sense, this makes sense, since I assumed x<-2, so the limit
doesn't make sense, as opposed to the y example. But should an error
maybe be raised instead? I assume this is how I am supposed to
interpret the output, but ? limit; doesn't indicate this either way.
Or should it not matter, as if x were treated as a dummy variable? In
which case I should get und. And does this occur sometimes in
integrals (I don't know)? Thank you as always for the help!