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Board Announcements (Altcoins)
Re: [ANN][GAP] Gapcoin - Prime Gap Search - New Math Algo - CPU / GPU - Zero Premine
by
pdazzl
on 30/06/2015, 20:52:04 UTC
CTR GapMiner Update

New Feature: Creating custom ctr files

The ctr algorithm is divided into 2 parts. The first part,
is a simple greedy algorithm which ties to find offsets
for each involved prime, so that the desired number range
has at least prime candidates as possible.

The second part is an evolutionary algorithm, which tries to improve the
results form the greedy algorithm. Therefor the greedy algorithm
will be executed several times with slightly different parameters, to produce
ctrs which differs in quality, which than can be used by the evolutionary algorithm.

The output is a text file which can be used by gapminer as an input for ctr sieving.

Parameter description:

Code:
--calc-ctr          Indicates that we want to calculate a ctr file.

--ctr-strength      This is used to variate the computing time spend
                    within the greedy algorithm. Higher strength
                    can yield better results.

--ctr-primes        The number of primes to use in the ctr file. The more
                    primes the better the ctr result, but the shift
                    also increases. Minimum shift can be calculated as
                    the binary logarithm of the product of all primes:
                    log2(p1 * p2 * ... *pn).

--ctr-evolution     Whether to use the evolutionary algorithm or not.

--ctr-fixed         This number indicates the number of starting primes
                    which wound get touched by the evolutionary algorithm
                    the offsets for the primes 2,3,5,7,11... are mostly
                    perfect computed by the greedy algorithm, and changing
                    them only declines the result.

--ctr-ivs           The number of individuals used in the evolutionary algorithm.
                    More increases computing time but mostly also the
                    result quality.

--ctr-range         Percent deviation from the number of primes.
                    Useful if you don't want to look for a specific number
                    of primes.

--ctr-bits          The shift value you later use for sieving has to be greater
                    than log2(p1*p2*..*pn). With this flag you can fine tune a specific
                    shift by setting this to shift - log2(p1*p2*..*pn).

--ctr-merit         The target merit (while testing the ctr it seamed that
                    sieving for target-merit - 1 yields the best results)

--ctr-file          The target ctr output file. You can open this with a
                    text editor. Look for the n_candidates value, the smaller
                    it is the better the ctr file.


windows: https://github.com/gapcoin/GapMiner/releases/download/crt-rev5.1/windows.zip
md5: 50b506c6fdacbe36dd2d87e6f2c296d9

linux: https://github.com/gapcoin/GapMiner/releases/download/crt-rev5.1/linux.zip
md5: 88f0a3975df728566d3500b69475a78a

source code: https://github.com/gapcoin/GapMiner/

I'm sorry to inform you, that I made mistake within the example commands.
At the --ctr-bits flag you have to subtract 256 from the given value.

The links above were updated.
Any already generated ctr files can still be used, but they are targeting a 0.25 (130 primes) till 4.7 (14 primes) times greater merit.

I was wondering why a shift 1024 was taking multiple days and counting Smiley  though I had set the ivs to 10000 and the target shift to 20.