# Petrus?



## fleeting_penguin (Sep 5, 2007)

Is the Petrus method worth learning as an intermediate step to Fridrich while I focus on blindsolving and bigger cubes? I seems like it takes a lot of practice making blocks to get sub minute times with it. Approximately what time can I expect in a week if I practice consistently? Is it even worth learning at all?

How many moves should I aim to do each step of Petrus in? I know for Fridrich F2L you should do each corner/edge pair in under 8 or look it up; what are some similar guidelines for Petrus in the blockbuilding stages?


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## griz (Sep 5, 2007)

are you going for speed or fewest moves?


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## fleeting_penguin (Sep 5, 2007)

griz said:


> are you going for speed or fewest moves?


Ultimately for an average speed under 30 seconds, and I want to know if Petrus can achieve this. Though I am wondering how long it will take to get sub 60, as that is what I really want to break.


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## fleeting_penguin (Sep 5, 2007)

Also, I really need some guidelines for the number of moves I should get under each time on the block building stages. I feel like those take a lot of time for me. Though I am sure it will get better with practice, it's just how much practice...


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## griz (Sep 5, 2007)

petrus can get sub 30. but block building takes practice. on the 2x2x2 block you should average 6 or 7 moves. 2x2x3 should take 7-8 moves


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## badmephisto (Sep 5, 2007)

Petrus is known to have very low number of moves solutions as opposed to Fridrich method, which I dont see as too much of an advantage, especially with all the finger tricks... so number of moves is not as much of a concern, as thinking time is. 
If you want to learn it only as an intermediate step, I would recommend against that... it is probably a waste of time that you could spend perfecting your Fridrich method - F2L or whatever.


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## pjk (Sep 5, 2007)

If I were you I'd aim for around 45 move avg with it, then work on speedsolving it. I'd actually work on Roux if I were you. Good luck.


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## MAHTI-ANSSI (Sep 5, 2007)

What? Johannes hasn't posted here?


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## AvGalen (Sep 5, 2007)

> What? Johannes hasn't posted here?


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## Johannes91 (Sep 5, 2007)

fleeting_penguin said:


> Is the Petrus method worth learning as an intermediate step to Fridrich


Eh, what do you mean? They are two very different methods. Petrus is more difficult and more advanced than Fridrich. I can't see how you would use it as an "intermediate step".

Move counts should be something like this:
Step 1: 5-6
Steps 2+3: 10-12
Step 4a: 6
Step 4b: 6

And whatever your LL takes.



fleeting_penguin said:


> Ultimately for an average speed under 30 seconds, and I want to know if Petrus can achieve this.


Yes, Petrus can achieve that. He averages 20-25 seconds as far as I know.



fleeting_penguin said:


> Though I am wondering how long it will take to get sub 60, as that is what I really want to break.


Took me a couple of weeks.


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## fleeting_penguin (Sep 5, 2007)

pjk said:


> If I were you I'd aim for around 45 move avg with it, then work on speedsolving it. I'd actually work on Roux if I were you. Good luck.


Why Roux over Petrus?

And why is Petrus harder than Fridrich? It seems like I trade learning a bunch of algorithms for needing to think on the go. I much prefer thinking.


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## Johannes91 (Sep 5, 2007)

fleeting_penguin said:


> It seems like I trade learning a bunch of algorithms for needing to think on the go.


Nope, there's no need to think any more than there's with Fridrich (in speedsolving). You need to develop a good intuition to be able to see which pieces you should solve and how, instead of memorizing solutions to all/most of the cases.


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## pjk (Sep 5, 2007)

Roux, in my mind, just seems to have the most potential right now.


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## fleeting_penguin (Sep 5, 2007)

Oh, now I'm torn by indecision. I will probably waste my time debating the virtues of each for a week before actually doing anything.

Which one will allow me to get faster times with less practice?


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## ExoCorsair (Sep 6, 2007)

fleeting_penguin said:


> Which one will allow me to get faster times with less practice?



Typical...

Why don't you try all the methods first? What's fast for one person may not be so fast for another... Also, you'd probably progress the most on the method that you like the most.

Anyhow. To answer your question, if you've been using CFOP, I'd say stick with that, because once you change methods, you WILL slow down at the beginning.

Remember that it will take a lot of practice to get down to sub-20 regardless of whichever method you end up using.


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## fleeting_penguin (Sep 6, 2007)

ExoCorsair said:


> Typical...
> 
> Why don't you try all the methods first? What's fast for one person may not be so fast for another... Also, you'd probably progress the most on the method that you like the most.
> 
> ...


I know it's rather blunt to ask which is faster and easier, but that's honestly want I want.

I don't really like CFOP all that much. That's why I wanted to explore alternative methods. Of course getting sub 20 is probably possible with any method, and it's going to take practice to get there with any method, but I wanted to explore Petrus because the LL seemed much easier than with Fridrich. I also wanted to explore the learning curve and results per time of each method, because realistically I'm probably not ever going to think of cubing as more than a (very) fun hobby and probably not practice enough to get sub 20, so having good results early on is something that is rather important, I guess.

Looking at Roux, I also see some tables of algs to memorize, so I think I'll start learning Petrus unless anything thinks Roux or some other alternative method is measurably better. And I'm very open to anything (corners first, whatever) as long as the results are good. Thoughts on this?

Thank you for the discussion thus far.


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## ExoCorsair (Sep 6, 2007)

fleeting_penguin said:


> but I wanted to explore Petrus because the LL seemed much easier than with Fridrich.



You can combine the three steps of Petrus LL from the 13 algorithms you need to two steps or even one step (which ends up being ZBLL).

Either way, it appears to me that most of the fastest solvers are that fast because of a very fast F2L. But you said that you probably are not thinking of going down to those sub-20 times.

However, I see Petrus and CFOP as similar because they both complete two layers and then finish the last layer (arguably, how each go about doing the two is relatively different, but that's not my point). I wonder why, if you are just interested in the LL, that you wouldn't solve F2L with cross + pairs and then use Petrus LL?

You could always try Heise... Not awesome for speedcubing, imo, but a rather interesting (and small move count) method. You know, just to be different.


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## fleeting_penguin (Sep 6, 2007)

Hmm. It seems I had overly romanticized notions of Petrus LL. Now I see the best way to just do Fridrich, just with a cut down OLL. Which is nice. But I could do the same thing with a 3 look LL.

So I guess there is no escaping memorizing those algs for the LL. 

Then, I have to ask, what is the point of Petrus? It seems like a slower way than Fridrich F2L, with more thought required. It and Roux also seem heavily dependent on inspection time to cut down on F2L time. I don't get inspection time when I tell people to scramble a cube and give it to me.

Though I do not have a speedcube, so maybe efficient solutions are better because I turn very slowly. The middle slices are pretty much impossible to turn. And I cannot perform any fingertricks faster than just turning the side normally, because of resistance.

So what would be your recommended course of action, and what would you recommend if I plan on being nonconformist and staying away from CFOP? Because I really don't want to be like everyone else. I have this stupid desire to be unique.

Many thanks.


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## tim (Sep 6, 2007)

fleeting_penguin said:


> Then, I have to ask, what is the point of Petrus? It seems like a slower way than Fridrich F2L, with more thought required. It and Roux also seem heavily dependent on inspection time to cut down on F2L time. I don't get inspection time when I tell people to scramble a cube and give it to me.



If you just want to impress people, learn a simple layer-by-layer method, practice a bit and execute it as fast as possible. That's much more impressive than solving a cube slow with much less moves and with a faster time.

I recommend to learn Petrus and Roux and play around with both methods at least a week. Then learn the method which feels "right" for you.


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## ExoCorsair (Sep 6, 2007)

cin said:


> I recommend to learn Petrus and Roux and play around with both methods at least a week. Then learn the method which feels "right" for you.



Roux really isn't an option unless he gets a new cube, apparently.

I suggest Heise, again (http://www.ryanheise.com/cube/).


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## fleeting_penguin (Sep 6, 2007)

But that's rather unsuitable for speedcubing. It's not that I want to be slow...

I guess I could do M turns by turning M and R both and then R' . It's way faster to do that then to get the necessary force with my thumb to squeeze that middle layer through.


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## Johannes91 (Sep 6, 2007)

pjk said:


> Roux, in my mind, just seems to have the most potential right now.


What are your times with Petrus and Roux? Just wondering.



fleeting_penguin said:


> Then, I have to ask, what is the point of Petrus? It seems like a slower way than Fridrich F2L, with more thought required.


Again, Petrus doesn't require any more thinking than Fridrich. Why does it seem slower to you?
And the point? It's a very clever method.



fleeting_penguin said:


> It and Roux also seem heavily dependent on inspection time to cut down on F2L time.


How much experience do you have with those methods? Inspection time is not very big deal IMO. I think you should just start practising instead of just speculating...



fleeting_penguin said:


> So what would be your recommended course of action, and what would you recommend if I plan on being nonconformist and staying away from CFOP?


I would recommend Heise, but I've got the impression that you aren't aren't very interested in puzzles but just want to get fast times quickly. So I recommend Petrus.


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## deadalnix (Sep 6, 2007)

The bad point in petrus compared with fridrich is the fingers tricks during F2L. But it's a very clever method (something beautiful in this method), and as a friend say's me : this methode respect the cube. It's a good method for speed and FMC.

Roux method is more effiscient in FMC than in speedcubing. This method has a great potential beaucause of it's flexibility during the solve.

For all these methods, you will need to practice a lot to get under 30.

I don't know heise method . . .


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## badmephisto (Sep 6, 2007)

I never got into Petrus too much, but I think I understand it, and I don't see how it can be better than Fridrich, even if you do the 2-look OLL, orienting edges first. The only advantage to doing what to me seems extra thinking to orient all the edges after you get 2x2x3 block is that when you are done the F2L you only have one of 7 cases. Well in Fridrich, most of the time you only need to flip 2 edges... and its a trivial F R U R' U' F' which is really fast (or its inverse). So taking care of edges is not a problem and takes only split second.

It also seems like Petrus is doing things too much piecewise... orienting edges and corners in separate stages etc, while in Fridrich all orientation and all permutation is reduced to one algorithm that takes usually anywhere around 2 seconds each. 

Like i said, i never actually got into Petrus, so i may be wrong, or I was looking at some beginner version of Petrus


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## fleeting_penguin (Sep 6, 2007)

Johannes91 said:


> Again, Petrus doesn't require any more thinking than Fridrich. Why does it seem slower to you?
> And the point? It's a very clever method.


I like cleverness too (I do AIME and USAMO stuff), but like badmephisto, based on my VERY limited experience and a few days practice, I find it worse for the reasons he stated.
Why would it be better than Fridrich? Don't get me wrong, if you can provide some evidence or argument that it is better Fridrich I'll hop right aboard the Petrus bandwagon. And you are right that I should practice more before asking stupid questions. I am sorry. I was just curious.


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## Jack (Sep 6, 2007)

I don't know much about Petrus, so I may be wrong, but I think that one of Petrus' advantages is that it uses fewer moves than Fridrich. Also, about the orienting edges, it does help because it makes the rest of the F2L (after the 2x2x3 block) completely 2 generator and very fast, and also lets you use COLL on the LL.


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## fleeting_penguin (Sep 6, 2007)

So then why does everyone (world class) use Fridrich, and not Petrus? Just personal preference?


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## pjk (Sep 7, 2007)

Johannes91 said:


> What are your times with Petrus and Roux? Just wondering.


Never timed Petrus, and for Roux around 30 seconds. Of course, I don't use proper technique of building blocks, orienting/permuting corners, etc. 

Just by looking at the steps involved, the recognition potential, and the move count, I think Roux has the most potential to be world class. I have not studied Heise yet, so I can't speak for it. For what I have seen though, it appears recognition would be a problem.

BTW, fleeting penguin, Anthony Hsu I believe uses Petrus and avg's sub-15.


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## fleeting_penguin (Sep 7, 2007)

What's wrong with corners first solutions? They seem cool also, and I am playing around with Waterman's method. Is Waterman the most optimized corners first one, or are there others?


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## griz (Sep 7, 2007)

what you could do to get a fast time is a petrus f2l and then do a coll then a pll so u would only have to learn 28 algs


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## ExoCorsair (Sep 7, 2007)

pjk said:


> BTW, fleeting penguin, Anthony Hsu I believe uses Petrus and avg's sub-15.



He uses Petrus F2L, then OLL/PLL.


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## AvGalen (Sep 7, 2007)

> what you could do to get a fast time is a petrus f2l and then do a coll then a pll so u would only have to learn 28 algs


 
Normally there are 40 COLL cases and 4 PLL cases after that. In this case it would be better to say:

Then do OLL (7)/PLL(21) where you only need to learn a small subset of the OLL-cases.


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## griz (Sep 7, 2007)

you do know when you finish petrus f2l it puts a cross on top right


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## AvGalen (Sep 7, 2007)

> you do know when you finish petrus f2l it puts a cross on top right


Yes, that is why I said "OLL (7)", "small subset of the OLL-cases" and "4 PLL cases"

COLL is a reference to a system that Orients and Permutes the corners of the last layer and requires 40 cases. If you use that you would need 40+4 instead of 7+21 cases.

[slightly_offtopic]Why is it called COLL and not CLL?
COLL is not an abreviation of Corner Orientation Last Layer. It is used to mean Corners Last Layer, just like ELL is meant to mean Edges Last Layer or am I making a mistake?[/slightly_offtopic]


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## Johannes91 (Sep 7, 2007)

fleeting_penguin said:


> So then why does everyone (world class) use Fridrich, and not Petrus? Just personal preference?


Why is Windows more popular than Linux?

Almost everybody recommends Fridrich. There have been threads where people ask questions about Petrus or Roux, but everybody just ignores those and tells them to learn LBL and then move on to Fridrich.

And people who don't know anything about Petrus keep saying things that aren't true and make it sound like a bad method.



pjk said:


> Anthony Hsu I believe uses Petrus and avg's sub-15.


I avg sub-15, too.



AvGalen said:


> Why is it called COLL and not CLL?


CLL doesn't preserve EO but COLL does. That's where the O comes from. OCLL could be used to mean Orient Corners of Last Layer.

There's also CMLL.


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## AvGalen (Sep 7, 2007)

> CLL doesn't preserve EO but COLL does. That's where the O comes from. OCLL could be used to mean Orient Corners of Last Layer.


 
Thanks. I think my confusion comes from my 4 look last layer:
Edge-Orientation Last Layer
Corner-Orientation Last Layer -> Also COLL, but I never use that abbreviation!
Corner-Permutation Last Layer
Edge-Permutation Last Layer

P.S. Don't get people going on a "Why is Windows more popular than Linux?" question please


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## griz (Sep 7, 2007)

Windoes i s alot more popular then linux. and most people recomend fridrich.like people recomend windows


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