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

Joined
Dec 11, 2009
Messages
294
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

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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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deepSubDiver

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Jun 17, 2009
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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

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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 :D

Is it "fixable"?
 

Caedus

Premium Member
Joined
Jul 11, 2009
Messages
378
Location
Edmonton, Canada
[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.
 

Faz

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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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