bits of underlying BRNG integer recurrence.
Generation method; the specific value is
Descriptor of the stream state structure.
Number of random values to be generated
nrandom integer numbers. If the
streamwas generated by a 64 or a 128-bit generator, each integer value is represented by two or four elements of
rrespectively. The number of bytes occupied by each integer is contained in the field
wordsizeof the structure
VSL_BRNG_PROPERTIES. The total number of bits that are actually used to store the value are contained in the field
nbitsof the same structure.
See Advanced Service Routines for a more detailed discussion of
vRngUniformBitsfunction 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
LCGonly 24 higher bits of an integer value can be considered random. See VS Notes for details.
Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.
Notice revision #20110804
This notice covers the following instruction sets: SSE2, SSE4.2, AVX2, AVX-512.
- VSL_ERROR_OK, VSL_STATUS_OK
- Indicates no error, execution is successful.
- streamis aNULLpointer.
- streamis not a valid random stream.
- Callback function for an abstract BRNG returns an invalid number of updated entries in a buffer, that is,< 0or>.nmax
- Callback function for an abstract BRNG returns 0 as the number of updated entries in a buffer.
- Period of the generator has been exceeded.
- Number of retries to generate a random number by using non-deterministic random number generator exceeds threshold.
- ARS-5 random number generator is not supported on the CPU running the application.