Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/5/84; site randvax.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!cornell!uw-beaver!tektronix!hplabs!sdcrdcf!randvax!fateman%ucbdali@Berkeley (Richard Fateman) From: fateman%ucbdali@Berkeley (Richard Fateman) Newsgroups: net.math.symbolic Subject: Re: Bug in Macsyma's definite integration ? Message-ID: <2661@randvax.UUCP> Date: Wed, 21-Aug-85 12:39:29 EDT Article-I.D.: randvax.2661 Posted: Wed Aug 21 12:39:29 1985 Date-Received: Sun, 25-Aug-85 13:25:40 EDT References: <256@watmum.UUCP> <2660@randvax.UUCP> Sender: lseward@randvax.UUCP Distribution: net Organization: Rand Corp., Santa Monica Lines: 33 > > (c1) integrate( exp(-t)/(1+t), t, 0, infinity ); > > INTEGRAL IS DIVERGENT > > > > /* This is wrong. Have I input the problem incorrectly ? */ > > /* Also, after 10 minutes on the following problem. */ > > > > (c2) integrate( exp(-t)/(1+t^(3/2)), t, 0, infinity ); > > NAME STACK OVERFLOW > > > > /* Am using the latest version on a VAX running Berkely UNIX BSD 4.2 */ > > ----forwarded message--- Received: from UCB-VAX.ARPA by rand-unix.ARPA; Tue, 20 Aug 85 14:45:37 pdt Received: from ucbdali.ARPA by UCB-VAX.ARPA (4.24/5.3) id AA01855; Tue, 20 Aug 85 14:43:16 pdt Received: by ucbdali.ARPA (5.5/4.48) id AA01115; Tue, 20 Aug 85 14:43:09 PDT Date: Tue, 20 Aug 85 14:43:09 PDT From: fateman%ucbdali@Berkeley (Richard Fateman) Message-Id: <8508202143.AA01115@ucbdali.ARPA> To: caviness@UDel-Dewey.ARPA Subject: Macsyma bugs? Cc: lseward@rand-unix.ARPA I got the same answers on a sun 2/50. It took only 35% longer to compute I think Monagan's problem was that he used "infinity", not "inf". "infinity" is complex infinity, not real positive infinity. If you want a simple bug, try Int[1/x^2,{x,-1,1}] in SMP. you get -2. Note the integrand is non-negative. The integral is divergent, as Macsyma is able to figure out. It seems to me that this is not the right place for bug reports, though. macsyma bugs can be mailed to macsym@mit-mc.arpa. Dunno about SMP, though.