Optimal 2x2 Scrambles for CCT (for versions <=0.9.4)

reThinking the Cube

Member
It just means that the programmer doesn't really understand what random-state refers to. It's also very very easy to generate a random position; I don't understand why you guys are using such convoluted methods. >_>
Hmm, is my randomCube() function a bit bloated?? I couldn't think of a more direct algorithm than that :confused:
Given that Jaap's solver just uses two numbers for the position, you should just be randomly generating those two numbers. I don't know what Dan did to modify the code for CCT, but this is how I generated a random position in the original scrambler:

int p = (int)(Math.random()*5040), o = (int)(Math.random()*729);
I am looking for a trustworthy source of info that shows the distribution for true random state positions (generated by this 2 random# method) according to the #of moves away from solved state. What % of positions generated this way will be 1,2,3,4,5.....11 moves away from solved at the completion of the scramble?

Cride5

It just means that the programmer doesn't really understand what random-state refers to. It's also very very easy to generate a random position; I don't understand why you guys are using such convoluted methods. >_>
Hmm, is my randomCube() function a bit bloated?? I couldn't think of a more direct algorithm than that :confused:
Given that Jaap's solver just uses two numbers for the position, you should just be randomly generating those two numbers. I don't know what Dan did to modify the code for CCT, but this is how I generated a random position in the original scrambler:

int p = (int)(Math.random()*5040), o = (int)(Math.random()*729);
I am looking for a trustworthy source of info that shows the distribution for true random state positions (generated by this 2 random# method) according to the #of moves away from solved state. What % of positions generated this way will be 1,2,3,4,5.....11 moves away from solved at the completion of the scramble?
p is just an index uniquely identifying all possible permutations of the 8 (actually 7) cubies, and o identifies all possible orientations. The Math.random() function generates random numbers in a uniform distribution between 0(inclusive) and 1(exclusive). Multiplying by 5040 means p will represent one out of every possible permutation with equal probability (similarly for o).

Jaap's script accepts the cube state in facelet form, so I wrote my randomCube() function to supply exactly that, but the search function itself converts this format into an index (the variables are called q and t). Bypassing the facelet format completely would indeed have been much simpler. Oh well..

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hr.mohr

Member
[offtopic but related]

Herbert Kociemba has made a java package of the 2-phase algorithm. Perhaps this could be used to make random state 3x3x3 scrambles as well?

Cride5

[offtopic but related]

Herbert Kociemba has made a java package of the 2-phase algorithm. Perhaps this could be used to make random state 3x3x3 scrambles as well?
Implementing 3x3 random-state scrambles in CCT sounds like a great idea. There's a already a java applet, and JS timer which does exactly that.

deepSubDiver

Member
It indeed is. Unfortunately it sometimes seems to cancel the search algorithm and throws exceptions instead of scrambles
Further than that, it sometimes needs a few seconds to generate the algorithm. I sometimes begin scrambling and just one or two seconds later the algorithm updates, while I was scrambling the old scramble once again.

Pedro

Member
It indeed is. Unfortunately it sometimes seems to cancel the search algorithm and throws exceptions instead of scrambles
Further than that, it sometimes needs a few seconds to generate the algorithm. I sometimes begin scrambling and just one or two seconds later the algorithm updates, while I was scrambling the old scramble once again.
So true

Is it "fixable"?

masterofthebass

that was back when we still used 25 random moves.

reThinking the Cube

Member
that was back when we still used 25 random moves.
WR: Javier Paris 2x2x2 1.63'' Murcia Open 2008

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

Is this scramble 25 random moves?

masterofthebass

looks a lot like it to me...

reThinking the Cube

Member
looks a lot like it to me...
Looks can be deceiving. Are you 100% sure that it is a 25 move RANDOM scramble?

Stefan

Member
CCT has 3x3 random-state scrambles? How do I activate them?

Caedus

[offtopic but related]

Herbert Kociemba has made a java package of the 2-phase algorithm. Perhaps this could be used to make random state 3x3x3 scrambles as well?
Implementing 3x3 random-state scrambles in CCT sounds like a great idea. There's a already a java applet, and JS timer which does exactly that.
I believe they are talk about implementing it in the future.

2x2 is the only random state scrambling I know of so far in CCT

I think the argument about whether the random-state scrambling was random or not was about a different scrambler.

shelley

chang
CCT has 3x3 random-state scrambles? How do I activate them?
CCT 0.9.5 has random state scrambles for 3x3. The last testing version I played with did, anyway (I'm still using an older version because 0.9.5 runs slower and uses more memory)

reThinking the Cube

Member
looks a lot like it to me...
Looks can be deceiving. Are you 100% sure that it is a 25 move RANDOM scramble?
a you 100% sure you aren't a RETARDED person?
Win. Go Dan!
Agreed.
Fail. That scramble only appears random to retards.
Lmao wtf. What is wrong with the scramble?
Lmao wtf. What is wrong with YOU? Are you pretending to be retarded too?

Hint: What is this? --> (U2 R2 B2 R2 U2 B2 R2)

(U2 R2 B2 R2 U2 B2 R2) = (B2)

I could expose the whole scramble, but then I would spoil it for all you wannabee pompous retards!

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