Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: Accounting for Parity in Memorization

  1. #1

    Default Accounting for Parity in Memorization

    I have not solved a cube blindfolded yet, though I can solve it with old pochmann while looking, so maybe this wouldn't work, but...

    At least for Old Pochmann (centers and edges) if there is an odd number of permutations there is a parity. Say you memorize edges first, realize there is an odd number of permutations to do, so you swap two corners in your corner memorization.

    For example:
    Scramble: F R2 F R U2 L2 R' D' B L U' R D U L D B2 F D F2 L2 F2 R D2 U'

    (Eric Limeback's way for memo)
    Edge Memo: "VJH XMRPX TLS"
    Corner Memo: W(DBL-corner) , B(UFR-corner), B(DFR-corner), G(UFL-corner)... etc.

    I notice now, that it would be easier to start with corners and adjust edge memorization rather than corner because of the strange sticker swapping of the Old Pochmann edge algs.

    Is there any reason, why I should NOT do this parity fix in memorization?

    EDIT: Oops, I either solved it wrong or memorized it wrong, but I think I messed up somehow, but not because of the parity fixing in the memorization. Don't assume this example to work.
    EDIT2: I think my memorization doesn't match my scramble either
    Last edited by Musturd; 03-09-2009 at 02:33 PM.
    Or you can just use ZZ.
    PB (non-lucky) ZZ solve: 23.61

  2. #2
    Member Gparker's Avatar
    Join Date
    Feb 2009
    Location
    suffolk,virginia
    YouTube
    baseballrg
    Posts
    774

    Default

    all you do is the R perm after edges or corners and you did an odd number. and you just tell yourself you have it and thats it, your not allowed to turn the cube during memo
    Or you can just use the best method.

  3. #3

    Default

    Doing the R-perm twice is a waste of time because it can be accounted for in memorization, right?
    Basically, that question is the whole point of this thread.
    Or you can just use ZZ.
    PB (non-lucky) ZZ solve: 23.61

  4. #4
    Member Gparker's Avatar
    Join Date
    Feb 2009
    Location
    suffolk,virginia
    YouTube
    baseballrg
    Posts
    774

    Default

    what? you only have to do it once unless you use M2, you can memo around it but that would be harder
    Or you can just use the best method.

  5. #5
    Member
    Join Date
    Nov 2006
    Location
    Karlsruhe, Germany
    WCA Profile
    2007HABE01
    YouTube
    cin9247
    Posts
    1,671

    Default

    Quote Originally Posted by Musturd View Post
    I notice now, that it would be easier to start with corners and adjust edge memorization rather than corner because of the strange sticker swapping of the Old Pochmann edge algs.
    Why do you have to adjust your memorization in the first place? I don't really get it.
    tim's PBs on Cubemania

  6. #6
    Member
    Join Date
    Apr 2007
    WCA Profile
    2007GOUL01
    YouTube
    cardologist
    Posts
    4,298

    Default

    Sure, you can do it. I've done it before.
    #

  7. #7
    Member byu's Avatar
    Join Date
    Dec 2008
    Location
    California
    WCA Profile
    2009YUBR01
    YouTube
    bldmaster
    Posts
    2,024

    Default

    OK, I understand now.

    The question is that wouldn't it be faster if you didn't do an R-Perm for parity and just memorized UFR and UBR swapped. So when you want to see what is at FRU, you really look at RBU, RUF to BRU, UFR to UBR, and vice versa.

    My answer is that yes, it's possible only if you use old pochmann, with M2/R2, it doesn't work that way. If you use M2/old pochman with corners first, then it works (swap UL and UB), with edges first it doesn't. Plus, it's harder to memo, so although you'll have a faster execution, you may have a slightly longer memorization.

  8. #8
    Member fanwuq's Avatar
    Join Date
    Dec 2007
    WCA Profile
    2008FANW01
    YouTube
    fanwuq
    Posts
    2,846

    Default

    I never do R perm, it's just stupid. It can actually be any alg that swaps the edges, so it could be doing J or Y perm again; but why? Just leave the last corner to finish later after you finish the edges.
    I do not treat it as a special thing to memo. I do visual corners and count while memorize; there's no need to waste memory.
    I solve computer cubes slowly. Best averages of 12: 2x2x2: 4.155 3x3x3: 14.74

  9. #9
    The Punchmaster DavidWoner's Avatar
    Join Date
    May 2008
    Location
    Kansas City, MO, USA
    WCA Profile
    2008WONE01
    YouTube
    vault312
    Posts
    3,936

    Default

    Quote Originally Posted by Gparker View Post
    what? you only have to do it once unless you use M2, you can memo around it but that would be harder
    you only have to do it once when you use M2 as well, just do U' F2 U M2 U' F2 U
    (3:11:06 PM) Kirjava: I'm also famous for being nice when presented with stupid questions
    My youtube and my website. Team # <3

  10. #10

    Default

    Why do you need to know offhand if the scramble is in an even or odd state? As you go along solving the cube, no matter what method - you will eventually realise it and do the appropriate fix. Turning an odd position to an even position in the beginning of a solve. I do not see the benefit to be honest

    Per

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •