Class AbstractXoRoShiRo128

    • Field Detail

      • SEED_SIZE

        private static final int SEED_SIZE
        Size of the state vector.
        See Also:
        Constant Field Values
      • JUMP_COEFFICIENTS

        private static final long[] JUMP_COEFFICIENTS
        The coefficients for the jump function.
      • LONG_JUMP_COEFFICIENTS

        private static final long[] LONG_JUMP_COEFFICIENTS
        The coefficients for the long jump function.
      • state0

        protected long state0
        State 0 of the generator.
      • state1

        protected long state1
        State 1 of the generator.
    • Constructor Detail

      • AbstractXoRoShiRo128

        AbstractXoRoShiRo128​(long[] seed)
        Creates a new instance.
        Parameters:
        seed - Initial seed. If the length is larger than 2, only the first 2 elements will be used; if smaller, the remaining elements will be automatically set. A seed containing all zeros will create a non-functional generator.
      • AbstractXoRoShiRo128

        AbstractXoRoShiRo128​(long seed0,
                             long seed1)
        Creates a new instance using a 2 element seed. A seed containing all zeros will create a non-functional generator.
        Parameters:
        seed0 - Initial seed element 0.
        seed1 - Initial seed element 1.
      • AbstractXoRoShiRo128

        protected AbstractXoRoShiRo128​(AbstractXoRoShiRo128 source)
        Creates a copy instance.
        Parameters:
        source - Source to copy.
    • Method Detail

      • setState

        private void setState​(long[] state)
        Copies the state from the array into the generator state.
        Parameters:
        state - the new state
      • getStateInternal

        protected byte[] getStateInternal()
        Creates a snapshot of the RNG state.
        Overrides:
        getStateInternal in class LongProvider
        Returns:
        the internal state.
      • next

        public long next()
        Specified by:
        next in interface RandomLongSource
        Returns:
        the next random value.
      • nextOutput

        protected abstract long nextOutput()
        Use the current state to compute the next output from the generator. The output function shall vary with respect to different generators. This method is called from next() before the current state is updated.
        Returns:
        the next output
      • jump

        public UniformRandomProvider jump()
        Creates a copy of the UniformRandomProvider and then advances the state of the current instance. The copy is returned.

        The current state will be advanced in a single operation by the equivalent of a number of sequential calls to a method that updates the state of the provider. The size of the jump is implementation dependent.

        Repeat invocations of this method will create a series of generators that are uniformly spaced at intervals of the output sequence. Each generator provides non-overlapping output for the length of the jump for use in parallel computations.

        The jump size is the equivalent of 264 calls to nextLong(). It can provide up to 264 non-overlapping subsequences.

        Specified by:
        jump in interface JumpableUniformRandomProvider
        Returns:
        A copy of the current state.
      • longJump

        public JumpableUniformRandomProvider longJump()
        Creates a copy of the JumpableUniformRandomProvider and then advances the state of the current instance. The copy is returned.

        The current state will be advanced in a single operation by the equivalent of a number of sequential calls to a method that updates the state of the provider. The size of the long jump is implementation dependent.

        Repeat invocations of this method will create a series of generators that are uniformly spaced at intervals of the output sequence. Each generator provides non-overlapping output for the length of the long jump for use in parallel computations.

        The returned copy may be jumped m / n times before overlap with the current instance where m is the long jump length and n is the jump length of the JumpableUniformRandomProvider.jump() method.

        The jump size is the equivalent of 296 calls to nextLong(). It can provide up to 232 non-overlapping subsequences of length 296; each subsequence can provide up to 232 non-overlapping subsequences of length 264 using the jump() method.

        Specified by:
        longJump in interface LongJumpableUniformRandomProvider
        Returns:
        A copy of the current state.
      • performJump

        final void performJump​(long[] jumpCoefficients)
        Perform the jump to advance the generator state. Resets the cached state of the generator.
        Parameters:
        jumpCoefficients - Jump coefficients.