vRngUniformBits
vRngUniformBits
Generates
bits of underlying BRNG integer recurrence.
Syntax
status
=
viRngUniformBits
(
method
,
stream
,
n
,
r
);
Include Files
- mkl.h
Input Parameters
Name | Type | Description |
|---|---|---|
method | const MKL_INT | Generation method; the specific value is
|
stream | VSLStreamStatePtr | Pointer to the stream state structure |
n | const MKL_INT | Number of random values to be generated |
Output Parameters
Name | Type | Description |
|---|---|---|
r | unsigned int* | 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 VS Notes for details.Optimization Notice
|
|---|
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.
Return Values
- VSL_ERROR_OK, VSL_STATUS_OK
- Indicates no error, execution is successful.
- VSL_ERROR_NULL_PTR
- streamis aNULLpointer.
- VSL_RNG_ERROR_BAD_STREAM
- streamis 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,< 0or>.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.
- VSL_RNG_ERROR_NONDETERM_NRETRIES_EXCEEDED
- Number of retries to generate a random number by using non-deterministic random number generator exceeds threshold.
- VSL_RNG_ERROR_ARS5_NOT_SUPPORTED
- ARS-5 random number generator is not supported on the CPU running the application.