Advanced Service Routine Data Types

The Advanced Service routines refer to a structure defining the properties of the basic generator.

This structure is described in Fortran 90 as follows:

TYPE VSL_BRNG_PROPERTIES
    INTEGER streamstatesize
    INTEGER nseeds
    INTEGER includeszero
    INTEGER wordsize
    INTEGER nbits
    INTEGER reserved(8) 
END TYPE VSL_BRNG_PROPERTIES

The following table provides brief descriptions of the fields engaged in the above structure:

Field Descriptions
Field	Short Description
Fortran: streamstatesize	The size, in bytes, of the stream state structure for a given basic generator.
Fortran: nseeds	The number of 32-bit initial conditions (seeds) necessary to initialize the stream state structure for a given basic generator.
Fortran: includeszero	Flag value indicating whether the generator can produce a random 0.
Fortran: wordsize	Machine word size, in bytes, used in integer-value computations. Possible values: 4, 8, and 16 for 32, 64, and 128-bit generators, respectively.
Fortran: nbits	The number of bits required to represent a random value in integer arithmetic. Note that, for instance, 48-bit random values are stored to 64-bit (8 byte) memory locations. In this case, wordsize/WordSize is equal to `8` (number of bytes used to store the random value), while nbits/NBits contains the actual number of bits occupied by the value (in this example, `48`).
Fortran: reserved(8)	Reserved for internal use.

Note

Using Advanced Service routines for defining generators is not supported for Fortran, but you can use the Fortran interface to get information about a previously-registered generator using vslGetBrngProperties.