4x4 Orientation parity

[badmephisto]

I just got my 4x4, and i was able to figure out the whole thing by myself, but i got stuck on a parity case where everything was solved and single "dedge" was flipped. After about 4 hours of trying to devise a commutator or find some witty way of doing it, i looked up a solution, and it is just a random long algorithm with no real symmetry to it. In that sense im glad that i gave up, because i would never derive it by myself.

My question is, is there a way to handle this parity intuitively somehow, using some commutator, or at least a (possibly longer) algorithm that can be understood intuitively? I don't care about speed for now.

 

[ShadenSmith]

I spent weeks working on that...no luck for me however. I just had to suck it up and learn the algorithm. As far as there being no symmetry in it, I had the same problem. I just eventually broke it down into small patterns that I found and memorized those.

Good luck

 

[TimMc]

I'm not sure what "dedge" is. Is it short for "Double Edge"? (i.e. edge pair)

If so, you could use: r2 B2 U2 l U2 r' U2 r U2 F2 r F2 l' B2 r2
See: Link

EDIT:
It's a long algorithm but once you remember it you can execute it pretty quickly. I remember it by grouping parts of the algorithm:
r2 B2 U2 (think "RBU")
l U2 r' (think "LUR")
U2 r U2 (think "URU")
F2 r F2 (think "FRF)
l' B2 r2 (think "LBR")

Tim.

 

[darkzelkova]

lol dang that means I won't be able to figure it out myself x.x

 

[jonny guitar]

I totally agree with "just a random long algorithm with no real symmetry to it" and I have a bugger of time remembering it. I am going to try Tim's idea cuz it looks promising.

 

[cmhardw]

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

 

[Radu]

i found it also hard to memorize that whole alg but now i got it

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

Very nice step for a beginner. i think what you just explained above might help many to solve the 4x4x4

 

[darkzelkova]

It also works for a 5x5 (the r U2 X5 thing)

 

[mrCage]

Hi

For centers first c/e where the parity is a dedge swap i agree that r2 B2 U2 l U2 r' U2 r U2 F2 r F2 l' B2 r2 is probably the best way (or Badie's equivalent one avoiding B turns.

For cage/K4 or other direct solving methods, (l'U2)*2 F2l'F2rU2r'U2l2 = (l'U2)*2 F2l'F2[r,U2]l2 is maybe the most flexible one (and shorter too). This one is also useful for block-swap on larger cubes. Check the effect of (l'(Uu)2)*2 F2l'F2[r,(Uu)2]l2

Alos both these algs work on any orbital. So they solve both orientation parities on a 6x6x6 for instance!! (ie swap on layers 3/4 or 2/5). Just use the respective layers.

-Per

 

[badmephisto]

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

thanks Chris that's exactly what i was looking for. It's not the fastest method, but i supposed it could be called intuitive, once you know about the odd/even inner slices thing. Thanks!

 

[shimu]

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

thanks Chris that's exactly what i was looking for. It's not the fastest method, but i supposed it could be called intuitive, once you know about the odd/even inner slices thing. Thanks!

Hi, I am very interested to solve parity problem intuitively instead of memorizing algo. Can you elaborate on the steps to follow after performing (r' U2)*4 r' ? Thanks in advance!

 

[Lucas Garron]

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

thanks Chris that's exactly what i was looking for. It's not the fastest method, but i supposed it could be called intuitive, once you know about the odd/even inner slices thing. Thanks!

Hi, I am very interested to solve parity problem intuitively instead of memorizing algo. Can you elaborate on the steps to follow after performing (r' U2)*4 r' ? Thanks in advance!

Pair again.
If I were doing parity intuitively, I'd do r + a 3-cycle of edges + some cycles of x-centers.

 

[shimu]

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

thanks Chris that's exactly what i was looking for. It's not the fastest method, but i supposed it could be called intuitive, once you know about the odd/even inner slices thing. Thanks!

Hi, I am very interested to solve parity problem intuitively instead of memorizing algo. Can you elaborate on the steps to follow after performing (r' U2)*4 r' ? Thanks in advance!

Pair again.
If I were doing parity intuitively, I'd do r + a 3-cycle of edges + some cycles of x-centers.

Thanks for the reply but... i am not sure what is "3-cycle of edges" or "cycles of x-centers"... I guess because I am not an expert (^^;

I solve 3x3 using layer method but i think there is some difference in my last layer. For last layer, my steps are:
1. Move the corners into place.
2. Flip the corners to right orientation.
3. Move the edge into place.
4. Flip the edge into right orentation.
I see that most people here do the edge first before doing the corners. Is that why I am not understanding your terms?

 

[ShadenSmith]

Mainly because we're talking about a 4x4x4, not a regular Rubik's Cube.

 

[Lucas Garron]

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

thanks Chris that's exactly what i was looking for. It's not the fastest method, but i supposed it could be called intuitive, once you know about the odd/even inner slices thing. Thanks!

Hi, I am very interested to solve parity problem intuitively instead of memorizing algo. Can you elaborate on the steps to follow after performing (r' U2)*4 r' ? Thanks in advance!

Pair again.
If I were doing parity intuitively, I'd do r + a 3-cycle of edges + some cycles of x-centers.

Thanks for the reply but... i am not sure what is "3-cycle of edges" or "cycles of x-centers"... I guess because I am not an expert (^^;

I solve 3x3 using layer method but i think there is some difference in my last layer. For last layer, my steps are:
1. Move the corners into place.
2. Flip the corners to right orientation.
3. Move the edge into place.
4. Flip the edge into right orentation.
I see that most people here do the edge first before doing the corners. Is that why I am not understanding your terms?

No.

 

[da25centz]

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

YES! That is exactly what I was looking for. its so similar to the PLL parity alg (at least in my mind) so it makes it easy to memorize. Thanks!!!

 

[hawkmp4]

Wow, this is OLD.

 

[uberCuber]

A more intuitive way to fix the orientation parity is to simply perform an odd number of quarter turns on the inner layers. You will most likely have the centers already solved at this point though, so I suggest to use the following cyclic way to break up the centers and fix them again.

(r' U2)*4 r' or written out that's r' U2 r' U2 r' U2 r' U2 r'

This breaks apart and restores the centers in the middle M slice, and does so in 5 quarter turns of the inner r layer, thus "fixing", or really changing, the parity of the wings from odd to even.

After this you will need to restore the 4 edge groups in the M slice that got destroyed. This can be done simply with commutators or with your regular edge pairing method.

This algorithm is far longer than the parity algorithm you found, but it is much more intuitive.

Chris

YES! That is exactly what I was looking for. its so similar to the PLL parity alg (at least in my mind) so it makes it easy to memorize. Thanks!!!

:fp

please don't bump a really old thread just to say thanks to someone for something they said 2 and a half years ago..

 

[da25centz]

oh WOW sorry. I didnt even look at the date, i found this when using the search box

 

[jiggy]

Forget old! This was a great read! Thanks for the bump! =)