Oops. Sorry. I was interpreting the issue backwards. I don't have an explanation; Luke needs to show his numbers. Or I need to be in the lab where I can run it on Ubuntu, which doesn't seem likely to be the issue anyway.
rac On Jan 4, 2011, at 1:26 PM, Carl Eastlund wrote: > Richard, > > We're not looking for an explanation of why the two numbers are > different. We're looking for an explanation of why, on Luke's > machine, unlike anybody else's here, they _aren't_ different. Somehow > I don't think portability issues in DrRacket are anybody's homework > assignment. So if you have an explanation, please share. :) > > Carl Eastlund > > On Tue, Jan 4, 2011 at 3:22 PM, Richard Cleis <rcl...@mac.com> wrote: >> I can explain it, but I don't know if it's revealing a solution. >> >> rac >> >> On Jan 4, 2011, at 12:32 PM, Stephen Chang wrote: >> >>> I get results similar to Carl. >>> >>> Welcome to DrRacket, version 5.0.1.7 [3m]. >>> Language: Intermediate Student. >>> #i-0.49746596003269394 >>> #i-0.4974659600326953 >>> #i-4974659600326939.0 >>> #i-4974659600326953.0 >>>> (equal? (sum (g-series #i1000)) (accu-sum (g-series #i1000))) >>> false >>>> (equal? (* 10e15 (sum (g-series #i1000))) (* 10e15 (accu-sum (g-series >>>> #i1000)))) >>> false >>>> >>> >>> >>> Luke, can you post the output you get? >>> >>> >>> >>> >>> On Tue, Jan 4, 2011 at 10:57 AM, Carl Eastlund <c...@ccs.neu.edu> wrote: >>>> >>>> On Tue, Jan 4, 2011 at 9:38 AM, Luke Jordan <luke.jor...@gmail.com> wrote: >>>>> All that code came straight out of the text, except that I used if instead >>>>> of cond. The sum, accu-sum, and g-series defs are all given. In your >>>> >>>> Ah, yes, now I see where the accumulator-based sum is. Sorry, my mistake. >>>> >>>>> results I see a difference. When I run it at home it's the same. I can >>>>> even (equal? (sum (listof number)) (accu-sum (listof number))) and get >>>>> true. >>>> >>>> No idea what's going on. Maybe someone else will have an idea. >>>> >>>> --Carl _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
