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HPL_xjumpm(3)                HPL Library Functions               HPL_xjumpm(3)


NAME

       HPL_xjumpm - Compute constants to jump in the random sequence.


SYNOPSIS

       #include "hpl.h"

       void HPL_xjumpm( const int JUMPM, int * MULT, int * IADD, int * IRANN,
       int * IRANM, int * IAM, int * ICM );


DESCRIPTION

       HPL_xjumpm computes  the constants  A and C  to jump JUMPM numbers in
       the random sequence: X(n+JUMPM) = A*X(n)+C.  The constants encoded in
       MULT and IADD  specify  how to jump from one entry in the sequence to
       the next.


ARGUMENTS

       JUMPM   (local input)           const int
               On entry,  JUMPM  specifies  the  number  of entries  in  the
               sequence to jump over. When JUMPM is less or equal than zero, A
               and C are not computed, IRANM is set to IRANN corresponding to
               a jump of size zero.

       MULT    (local input)           int *
               On entry, MULT is an array of dimension 2,  that contains the
               16-lower  and 15-higher bits of the constant  a  to jump from
               X(n) to X(n+1) = a*X(n) + c in the random sequence.

       IADD    (local input)           int *
               On entry, IADD is an array of dimension 2,  that contains the
               16-lower  and 15-higher bits of the constant  c  to jump from
               X(n) to X(n+1) = a*X(n) + c in the random sequence.

       IRANN   (local input)           int *
               On entry, IRANN is an array of dimension 2. that contains the
               16-lower and 15-higher bits of the encoding of X(n).

       IRANM   (local output)          int *
               On entry,  IRANM  is an array of dimension 2.   On exit, this
               array  contains respectively  the 16-lower and 15-higher bits
               of the encoding of X(n+JUMPM).

       IAM     (local output)          int *
               On entry, IAM is an array of dimension 2. On exit, when JUMPM
               is  greater  than  zero,  this  array  contains  the  encoded
               constant  A  to jump from  X(n) to  X(n+JUMPM)  in the random
               sequence. IAM(0:1)  contains  respectively  the  16-lower and
               15-higher  bits  of this constant  A. When  JUMPM  is less or
               equal than zero, this array is not referenced.

       ICM     (local output)          int *
               On entry, ICM is an array of dimension 2. On exit, when JUMPM
               is  greater  than  zero,  this  array  contains  the  encoded
               constant  C  to jump from  X(n)  to  X(n+JUMPM) in the random
               sequence. ICM(0:1)  contains  respectively  the  16-lower and
               15-higher  bits  of this constant  C. When  JUMPM  is less or
               equal than zero, this array is not referenced.


SEE ALSO

       HPL_ladd (3), HPL_lmul (3), HPL_setran (3), HPL_jumpit (3),
       HPL_rand (3).

HPL 2.1                        October 26, 2012                  HPL_xjumpm(3)

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