From @mail.uunet.ca:mark.longridge@canrem.com Sat Jan 7 00:14:01 1995 Return-Path: <@mail.uunet.ca:mark.longridge@canrem.com> Received: from seraph.uunet.ca (uunet.ca) by life.ai.mit.edu (4.1/AI-4.10) for /com/archive/cube-lovers id AA03726; Sat, 7 Jan 95 00:14:01 EST Received: from portnoy.canrem.com ([198.133.42.17]) by mail.uunet.ca with SMTP id <124324-5>; Sat, 7 Jan 1995 00:14:52 -0500 Received: from canrem.com by portnoy.canrem.com (4.1/SMI-4.1) id AA10958; Sat, 7 Jan 95 00:10:54 EST Received: by canrem.com (PCB-UUCP 1.1f) id 1C791B; Fri, 6 Jan 95 23:57:55 -0500 To: cube-lovers@life.ai.mit.edu Reply-To: CRSO.Cube@canrem.com Sender: CRSO.Cube@canrem.com Subject: More cube terms From: mark.longridge@canrem.com (Mark Longridge) Message-Id: <60.940.5834.0C1C791B@canrem.com> Date: Fri, 6 Jan 1995 23:53:00 -0500 Organization: CRS Online (Toronto, Ontario) Notes on Notation and Terminology for Rubik's Cube -------------------------------------------------- In the "Handbook of Cubik Math": cubicles are in lower case, cubies are in UPPER CASE. If we use the 6 letters to describe the 6 faces and the various pieces and positions, e.g. UR, UF, UL, UB are the 4 edge pieces of the U face and URF, UFL, ULB, UBR are the 4 corner pieces. We agree to list the facelets at a corner in clockwise order. This gives the following edge & corner cubicles: uf, ul, ub, ur, rf, fl, lb, br, df, dl, db, dr urf, ufl, ulb, ubr, dfr, dlf, dbl, drb and the following edge & corner cubies: UF, UL, UB, UR, RF, FL, LB, BR, DF, DL, DB, DR URF, UFL, ULB, UBR, DFR, DLF, DBL, DRB By adhering to these conventions we can establish a standard notation for cube positions. The sequence R2 U3 F1 B3 R2 F3 B1 U3 R2 (9 q+h, 12 q) generates a 3-cycle of edges. The cycle representation of this sequence would be ( UF, UR, UB ) in ( ur, ub, uf). Thus cubie UF resides in cubicle ur cubie UR resides in cubicle ub cubie UB resides in cubicle uf If we assume that the unreferenced cubies are in proper position and orientation we have enough information to completely describe a cube in a way which provides more information on it's cycle structure. If an edge pair is flipped we refer to ( FU, LU ) in ( uf, ul) If a corner triple is twisted clockwise we refer to ( RFU, FLU, LBU ) in ( urf, ufl, ulb ) Here are a couple more examples: The super-flip has a cycle representation of ( FU, LU, BU, RU, FR, LF, BL, RB, FD, LD, BD, RD ) ( uf, ul, ub, ur, rf, fl, lb, br, df, dl, db, dr ) The 6 X order 3 has a cycle representation of (( FR, FU, UR ) ( BR, FD, LU ) (BU, RD, FL ) ( BD, DL, BL)) (( uf, ur, rf ) ( df, ul, br ) (dr, fl, ub ) ( dl, lb, db)) -> Mark <- Email: mark.longridge@canrem.com P.S. I'm not certain if the previously mentioned Rubik Algebra uses something like this, but I am going to add it to my cube program.