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    The two seeds are the Tausworthe and congruence long integers,
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    The two seeds are the Tausworthe and congruence long integers,
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    respectively.  A one-to-one mapping to S's \code{.Random.seed[1:12]}
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    respectively.  A one-to-one mapping to S's \code{.Random.seed[1:12]}
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    is possible but we will not publish one, not least as this generator
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    is possible but we will not publish one, not least as this generator
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    is \bold{not} exactly the same as that in recent versions of S-PLUS.}
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    is \bold{not} exactly the same as that in recent versions of S-PLUS.}
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    \item{\code{"Mersenne-Twister":}}{
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    \item{\code{"Mersenne-Twister"}:}{
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      From Matsumoto and Nishimura (1998). A twisted GFSR with period
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      From Matsumoto and Nishimura (1998). A twisted GFSR with period
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      \eqn{2^{19937} - 1}{2^19937 - 1} and equidistribution in 623
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      \eqn{2^{19937} - 1}{2^19937 - 1} and equidistribution in 623
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      consecutive dimensions (over the whole period).  The \sQuote{seed} is a
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      consecutive dimensions (over the whole period).  The \sQuote{seed} is a
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      624-dimensional set of 32-bit integers plus a current position in
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      624-dimensional set of 32-bit integers plus a current position in
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      that set.
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      that set.
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    }
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    }
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    \item{\code{"Knuth-TAOCP-2002":}}{
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    \item{\code{"Knuth-TAOCP-2002"}:}{
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      A 32-bit integer GFSR using lagged Fibonacci sequences with
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      A 32-bit integer GFSR using lagged Fibonacci sequences with
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      subtraction.  That is, the recurrence used is
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      subtraction.  That is, the recurrence used is
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      \deqn{X_j = (X_{j-100} - X_{j-37}) \bmod 2^{30}%
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      \deqn{X_j = (X_{j-100} - X_{j-37}) \bmod 2^{30}%
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      }{X[j] = (X[j-100] - X[j-37]) mod 2^30}
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      }{X[j] = (X[j-100] - X[j-37]) mod 2^30}
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      and the \sQuote{seed} is the set of the 100 last numbers (actually
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      and the \sQuote{seed} is the set of the 100 last numbers (actually
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      recorded as 101 numbers, the last being a cyclic shift of the
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      recorded as 101 numbers, the last being a cyclic shift of the
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      buffer).  The period is around \eqn{2^{129}}{2^129}.
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      buffer).  The period is around \eqn{2^{129}}{2^129}.
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    }
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    }
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    \item{\code{"Knuth-TAOCP":}}{
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    \item{\code{"Knuth-TAOCP"}:}{
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      An earlier version from Knuth (1997).
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      An earlier version from Knuth (1997).
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      The 2002 version was not backwards compatible with the earlier
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      The 2002 version was not backwards compatible with the earlier
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      version: the initialization of the GFSR from the seed was altered.
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      version: the initialization of the GFSR from the seed was altered.
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      \R did not allow you to choose consecutive seeds, the reported
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      \R did not allow you to choose consecutive seeds, the reported
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      \sQuote{weakness}, and already scrambled the seeds.
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      \sQuote{weakness}, and already scrambled the seeds.
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      Initialization of this generator is done in interpreted \R code
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      Initialization of this generator is done in interpreted \R code
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      and so takes a short but noticeable time.
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      and so takes a short but noticeable time.
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    }
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    }
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    \item{\code{"L'Ecuyer-CMRG":}}{
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    \item{\code{"L'Ecuyer-CMRG"}:}{
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      A \sQuote{combined multiple-recursive generator} from L'Ecuyer
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      A \sQuote{combined multiple-recursive generator} from L'Ecuyer
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      (1999), each element of which is a feedback multiplicative
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      (1999), each element of which is a feedback multiplicative
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      generator with three integer elements: thus the seed is a (signed)
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      generator with three integer elements: thus the seed is a (signed)
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      integer vector of length 6. The period is around
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      integer vector of length 6. The period is around
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      \eqn{2^{191}}{2^191}.
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      \eqn{2^{191}}{2^191}.
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      This is not particularly interesting of itself, but provides the
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      This is not particularly interesting of itself, but provides the
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      basis for the multiple streams used in package \pkg{parallel}.
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      basis for the multiple streams used in package \pkg{parallel}.
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      % See \code{\link{RngStream}}.
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      % See \code{\link{RngStream}}.
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    }
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    }
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    \item{\code{"user-supplied":}}{
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    \item{\code{"user-supplied"}:}{
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      Use a user-supplied generator.  See \code{\link{Random.user}} for
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      Use a user-supplied generator.  See \code{\link{Random.user}} for
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      details.
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      details.
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    }
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    }
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  }
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  }
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