vRngUniformBits

Generates bits of underlying BRNG integer recurrence.

Syntax

FORTRAN:

status = virnguniformbits( method, stream, n, r )

status = viRngUniformBits( method, stream, n, r );

Include Files

FORTRAN 77: mkl_vsl.f77
Fortran 90: mkl_vsl.f90
C: mkl_vsl_functions.h

Input Parameters

Name	Type	Description
method	FORTRAN 77: INTEGER Fortran 90: INTEGER, INTENT(IN) C: const int	Generation method; the specific value is `VSL_RNG_METHOD_UNIFORMBITS_STD`
stream	FORTRAN 77: INTEGER4 stream(2) Fortran 90:* TYPE (VSL_STREAM_STATE), INTENT(IN) C: VSLStreamStatePtr	Fortran: Descriptor of the stream state structure. C: Pointer to the stream state structure
n	FORTRAN 77: INTEGER Fortran 90: INTEGER, INTENT(IN) C: const int	Number of random values to be generated

Name

Type

Description

method

FORTRAN 77: INTEGER

Fortran 90: INTEGER, INTENT(IN)

C: const int

Generation method; the specific value is VSL_RNG_METHOD_UNIFORMBITS_STD

stream

FORTRAN 77: INTEGER*4 stream(2)

Fortran 90: TYPE (VSL_STREAM_STATE), INTENT(IN)

C: VSLStreamStatePtr

Fortran: Descriptor of the stream state structure.

C: Pointer to the stream state structure

FORTRAN 77: INTEGER

Fortran 90: INTEGER, INTENT(IN)

C: const int

Number of random values to be generated

Output Parameters

Name	Type	Description
r	FORTRAN 77: INTEGER4 Fortran 90:* INTEGER(KIND=4), INTENT(OUT) C: unsigned int*	Fortran: Vector of `n` random integer numbers. If the `stream` was generated by a 64 or a 128-bit generator, each integer value is represented by two or four elements of `r` respectively. The number of bytes occupied by each integer is contained in the field `wordsize` of the structure VSL_BRNG_PROPERTIES. The total number of bits that are actually used to store the value are contained in the field `nbits` of the same structure. See Advanced Service Routines for a more detailed discussion of VSLBRngProperties. C: Vector of `n` random integer numbers. If the `stream` was generated by a 64 or a 128-bit generator, each integer value is represented by two or four elements of `r` respectively. The number of bytes occupied by each integer is contained in the field `WordSize` of the structure VSLBRngProperties. The total number of bits that are actually used to store the value are contained in the field `NBits` of the same structure.See Advanced Service Routines for a more detailed discussion of VSLBRngProperties.

Name

Type

Description

FORTRAN 77: INTEGER*4

Fortran 90: INTEGER(KIND=4), INTENT(OUT)

C: unsigned int*

Fortran: Vector of n random integer numbers. If the stream was generated by a 64 or a 128-bit generator, each integer value is represented by two or four elements of r respectively. The number of bytes occupied by each integer is contained in the field wordsize of the structure VSL_BRNG_PROPERTIES. The total number of bits that are actually used to store the value are contained in the field nbits of the same structure. See Advanced Service Routines for a more detailed discussion of VSLBRngProperties.

C: Vector of n random integer numbers. If the stream was generated by a 64 or a 128-bit generator, each integer value is represented by two or four elements of r respectively. The number of bytes occupied by each integer is contained in the field WordSize of the structure VSLBRngProperties. The total number of bits that are actually used to store the value are contained in the field NBits of the same structure.See Advanced Service Routines for a more detailed discussion of VSLBRngProperties.

Description

The vRngUniformBits function generates integer random values with uniform bit distribution. The generators of uniformly distributed numbers can be represented as recurrence relations over integer values in modular arithmetic. Apparently, each integer can be treated as a vector of several bits. In a truly random generator, these bits are random, while in pseudorandom generators this randomness can be violated. For example, a well known drawback of linear congruential generators is that lower bits are less random than higher bits (for example, see [Knuth81]). For this reason, care should be taken when using this function. Typically, in a 32-bit LCG only 24 higher bits of an integer value can be considered random. See VSL Notes for details.

Return Values

VSL_ERROR_OK, VSL_STATUS_OK: Indicates no error, execution is successful.
VSL_ERROR_NULL_PTR: stream is a NULL pointer.
VSL_RNG_ERROR_BAD_STREAM: stream is not a valid random stream.
VSL_RNG_ERROR_BAD_UPDATE: Callback function for an abstract BRNG returns an invalid number of updated entries in a buffer, that is, < 0 or > nmax.
VSL_RNG_ERROR_NO_NUMBERS: Callback function for an abstract BRNG returns 0 as the number of updated entries in a buffer.
VSL_RNG_ERROR_QRNG_PERIOD_ELAPSED: Period of the generator has been exceeded.