Message #789

From: Roice Nelson <roice3@gmail.com>
Subject: Re: [MC4D] 3^4 in 386 twists
Date: Wed, 18 Nov 2009 00:47:04 -0600

Hi Klaus,

Nicely done - as this is only your second attempt, I’m getting the feeling
the run of the current record may be nearing its end! Just like you
observed, twist-length has been inversely proportional to time-length for my
record attempts too. I remember the sub-300 effort occupying my evenings
for a few weeks.

Here’s one tip that might help squeeze out a few more moves… On the step
boundaries, try to get a little head start on the next step when completing
the prior one. For example, I would try to get at least one or two 4C
pieces solved when doing the last couple 3C sequences (since I think you
aren’t using the same method, this may not apply exactly, but you get the
idea). This sounds more difficult than it is, and just cutting out one
required sequence can save a significant number of moves.

By the way, I entered your keyboard controls request as issue
93<http://code.google.com/p/magiccube4d/issues/detail?id=93> for
you. I think the correct approach when asked to change defaults like this
is often to make the program configurable, in this case to provide a way for
the user to map keyboard shortcuts to whatever values they want. Otherwise,
some will inevitably be disappointed by the choices made. Unfortunately,
since this is a post-4.0 feature, you’ll just need to be careful in the mean
time.

You also mentioned user prompts when saving. A request to be more defensive
when saving log files is issue
39<http://code.google.com/p/magiccube4d/issues/detail?id=39>,
but the thought recorded there right now is to only warn the user in certain
situations (as there are annoyance downsides to warning every time). Feel
free to share any further ideas on that one.

Take Care,
Roice

On Tue, Nov 17, 2009 at 2:45 PM, Klaus <klaus.weidinger@yahoo.com> wrote:

> Hi everyone!
>
> I finally finished my second solve today and I needed 386 twists. Of course
> I also have to thank Matthew for helping me with some parity cases.
> Especially the second one was really helpful.
>
> But I have to say that the closer I come to Roice’s record, the more I have
> to acknowledge what a good job he has done. And if I compare my solves I
> think it will really be hard to cut away another 88 twists. Well, of course
> there was a parity which used up 22 twists and if I’m lucky I won’t encouter
> this in my next solve. But the rest of this 88 twists will almost be
> impossible to cut away with just solving even more carefully.
>
> So here is a little comparison of my two solves:
> 1. step: I really made improvements here and managed to go from 323 twists
> down to 76 or, with disregard to the parity, 54. That is a reduction of
> 76.5% (83.3%) and I’m really content with this step. I don’t think I can
> make any further improvements here.
>
> 2. step: Here I needed 306 twists in my first solve and reduce it to 181
> twists (-40.8%). But I didn’t improve my system. I just did this step really
> bad in my first solve because I only wanted to finish the 3^4 fast. But I
> think if I want to beat the 300 twists, I have to change my system here.
>
> [ ;-) While writing this post I had an idea how to change my system. If it
> gets more efficient by this - or at least efficient enough - I can’t tell,
> but I do have a really good feeling about this. ;-) ]
>
> 3. step: This step is the same as solving the 3^3, just with two little
> parities which both need about 5 twists to get them done. In this step I
> made the fewest improvements and so I only got down from 146 to 129 twists
> (-11.6%). However, I can’t really improve here either because if I only
> count the twists I needed for the solution of the 3^3 I used up 70 quarter
> twists, however I had many half turns in there, so it perhaps was about
> 50-55 twists in half turn metric, which is really good with my system.
>
> I think I will start another solve tomorrow, but this could take even
> longer than my second one, because, despite the fact that I reduce twists,
> the solution proceeds slower and I get less and less time due to school.
>
> btw: I broke Remi’s record on the {3}x{3} 2. I only needed 5 turns within
> my 5th try (I solved roughly 5 out of 10 scrambled "cubes"). However, I
> don’t think he will wait long to start pressing "Ctrl + F" all over again as
> he did with the simplex last time ;-)
>
> Have a nice twist,
> Klaus
>
>
>
> ————————————
>
> Yahoo! Groups Links
>
>
>
>