Class Hart_Fast2Mult2

java.lang.Object
de.tilman_neumann.jml.factor.FactorAlgorithm
de.tilman_neumann.jml.factor.hart.Hart_Fast2Mult2

public class Hart_Fast2Mult2
extends FactorAlgorithm
A variant of class Hart_Fast2Mult that is about 10% faster in the long end.
  • Field Summary

    Fields inherited from class de.tilman_neumann.jml.factor.FactorAlgorithm

    NUM_PRIMES_FOR_31_BIT_TDIV, tdivLimit
  • Constructor Summary

    Constructors
    Constructor Description
    Hart_Fast2Mult2​(boolean doTDivFirst)
    Full constructor.
  • Method Summary

    Modifier and Type Method Description
    long findSingleFactor​(long N)
    Find a factor of long N.
    java.math.BigInteger findSingleFactor​(java.math.BigInteger N)
    Find a single factor of the given N, which is composite and odd.
    java.lang.String getName()  
    static void main​(java.lang.String[] args)
    Test.

    Methods inherited from class de.tilman_neumann.jml.factor.FactorAlgorithm

    factor, factor, getDefault, searchFactors

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • Hart_Fast2Mult2

      public Hart_Fast2Mult2​(boolean doTDivFirst)
      Full constructor.
      Parameters:
      doTDivFirst - If true then trial division is done before the Hart loop. This is recommended if arguments N are known to have factors < cbrt(N) frequently. With doTDivFirst=false, this implementation is pretty fast for hard semiprimes. But the smaller possible factors get, it will become slower and slower.
  • Method Details

    • getName

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

      public java.math.BigInteger findSingleFactor​(java.math.BigInteger N)
      Description copied from class: FactorAlgorithm
      Find a single factor of the given N, which is composite and odd.
      Specified by:
      findSingleFactor in class FactorAlgorithm
      Parameters:
      N - number to be factored.
      Returns:
      factor
    • findSingleFactor

      public long findSingleFactor​(long N)
      Find a factor of long N.
      Parameters:
      N -
      Returns:
      factor of N
    • main

      public static void main​(java.lang.String[] args)
      Test.
      Parameters:
      args - ignored