Package de.tilman_neumann.jml.factor.siqs

Class SIQS_Small

  • public class SIQS_Small
extends FactorAlgorithm
    Single-threaded SIQS implementation used to factor the Q(x)-rests in the trial division stage of SIQS/PSIQS. So far, the main purpose of this class is to prevent excessive logging when AnalysisOptions.ANALYZE == true and SIQS trial division starts to use an nested SIQS to factor large Q rests. A second purpose would be to optimize this class for the factorization of small N (say, below 100 bit).
    Author:
    Tilman Neumann

    • Constructor Detail

      • SIQS_Small

        public SIQS_Small​(float Cmult,
                  float Mmult,
                  Integer wantedQCount,
                  Float maxQRestExponent,
                  SIQSPolyGenerator polyGenerator,
                  int extraCongruences,
                  boolean permitUnsafeUsage)
        Standard constructor.
        Parameters:
        Cmult - multiplier for prime base size
        Mmult - multiplier for sieve array size
        wantedQCount - the wanted number of q whose product gives the a-parameter
        maxQRestExponent - A Q with unfactored rest QRest is considered smooth if QRest <= N^maxQRestExponent. Good values are 0.16..0.19; null means that it is determined automatically.
        polyGenerator -
        extraCongruences - the number of surplus congruences we collect to have a greater chance that the equation system solves.
        permitUnsafeUsage - if true then SIQS_Small uses a sieve exploiting sun.misc.Unsafe features. This may be ~10% faster.

    • Method Detail

      • getName

        public String getName()
        Specified by:
        getName in class FactorAlgorithm
        Returns:
        The name of the algorithm, possibly including important parameters.

      • searchFactors

        public void searchFactors​(FactorArguments args,
                          FactorResult result)
        Description copied from class: FactorAlgorithm
        Try to find at least one factor of the given args.N, which is composite and odd. This is a default implementation for algorithms that will only find a single factor or none at all. For sub-algorithms that may find more factors at once this method should be overwritten appropriately.
        Overrides:
        searchFactors in class FactorAlgorithm
        result - the result of the factoring attempt. Should be initialized only once by the caller to reduce overhead.

      • cleanUp

        public void cleanUp()
        Clean up after a factorization of N.

      • main

        public static void main​(String[] args)
        Stand-alone test.
        Parameters:
        args - ignored Some test numbers: 11111111111111111111111111 5679148659138759837165981543 11111111111111111111111111155555555555111111111111111 2900608971182010301486951469292513060638582965350239259380273225053930627446289431038392125 = 33333 * 33335 * 33337 * 33339 * 33341 * 33343 * 33345 * 33347 * 33349 * 33351 * 33353 * 33355 * 33357 * 33359 * 33361 * 33363 * 33367 * 33369 * 33369 * 33371 15841065490425479923 = 2604221509 * 6082841047