Hi! Im not saying there isn't a way to see parity other than counting cycles. All i was saying is that im quite sure it wouldn't be worth the effort. In general im also sceptical about most kinds of tricks/anticipation to avoid "hard cases" later on. For that reason im also sceptical whether the ZB-method in one form or another can really be faster than pure Fridrich/CFOP. I don't think anyone has proven yet, timewise, the advantages of a more complex method than pure CFOP. Of course there are the occasional really fast solves with it, but i haven't seen averages with pure ZB/VH or similar that compare with the fastest pure CFOP averages. This could of course be simply because only a few people are really into zb, and also that so far they only master a part of it :-)
I'm only happy to be proven wrong :-) -Per > --- In [email protected], "Ron van Bruchem" <[EMAIL PROTECTED]> wrote: > > Hi friends, > > Could Chris/Per/Stefan please explain why they think there cannot be a method other than counting cycles? > I would love to see a proof! Or better, I would love to see a proof of a better method. :-) > > Yesterday I found a counter example of my factor 4 hypothesis: just swap the edge cubies UrF and URb. You have 0 flipped edge pieces, but you do have parity. > When I started this solve the total number of flipped edge pieces was 14 (=parity, which was the indeed the case), so somewhere in the solve it changed to a factor of 4. > > CLL=>ELL is indeed an interesting approach. :-) > > Orientation parity during F2L was an idea I already had, and I asked Jaap to find an algorithm for it, using his program. At the moment he is still on tour in Florida. :-) > > Stefan, I don't understand what you mean with your idea about dedges. > > Doing both parities in one is interesting. At the moment I use two algorithms (the normal one by Chris, and the double parity one by Frédérick), but both twist corners because I use multislice moves. It would be great to have a fast algorithm that does not twist corners... It would be great to have a fast algorithm for the orientation parity anyhow. Yuki can do the parity algorithm amazingly fast. I need to train for that. :-) > > Is it true that once you solved 3 centers, you cannot change parity anymore when you keep these centers intact? Because then the center positions are fixed? > In that case you only have to count the parity during the first three centers. Which is not a big task. > > Thanks and have fun, > > Ron > > ----- Original Message ----- > From: Stefan Pochmann > To: [email protected] > Sent: Sunday, November 13, 2005 4:08 AM > Subject: [Speed cubing group] Re: 4x4x4 parity without counting cycles > > > --- In [email protected], "Ron" <[EMAIL PROTECTED]> wrote: > > > > One of the subjects was avoiding the orientation parity, as already > > investigated by Chris Hardwick. > > I really think there must be an easier way to check this parity, > > than to count the cycles. Counting cycles takes quite a lot of time, > > because you have to follow all pieces around the cube. > > I don't think there's an easy way out and like Per I don't think it > would be worth it anyway unless maybe you can really see it in 5- 10 > seconds. > > Some in my opinion more realistic time-savers dealing with the > parities in a centers>edges>3x3 method: > > - Do CLL->ELL, solving both parities as part of ELL. It's an easy > 2-look LL. > > - Recognize and fix orientation parity before solving the last F2L > pair. Chris should already be able to recognize it since he's doing > ZBF2L and it's not hard to learn anyway. Now we just need a fast alg > that exploits the unsolved slot. Should be shorter/faster than what we > have so far. > > - While pairing up dedges, don't flip built dedges anymore (optimally > don't change them at all) and count flipped dedges. Then you could fix > the parity before starting the 3x3 step. An even shorter/faster alg > should exist. > > Cheers! > Stefan > > > > > > > > ------------------------------------------------------------------- ----------- > YAHOO! GROUPS LINKS > > a.. Visit your group "speedsolvingrubikscube" on the web. > > b.. To unsubscribe from this group, send an email to: > [EMAIL PROTECTED] > > c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. > > > ------------------------------------------------------------------- ----------- > > > > [Non-text portions of this message have been removed] > ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/MXMplB/TM --------------------------------------------------------------------~-> Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/speedsolvingrubikscube/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
