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Lagged Fibonacci Generator
A Lagged Fibonacci generator (LFG or sometimes LFib) is an example of a pseudorandom number generator. This class of random number generator is aimed at being an improvement on the 'standard' linear congruential generator. These are based on a generalisation of the Fibonacci sequence. The Fibonacci sequence may be described by the recurrence relation: :S_n = S_ + S_ Hence, the new term is the sum of the last two terms in the sequence. This can be generalised to the sequence: :S_n \equiv S_ \star S_ \pmod, 0 < j < k In which case, the new term is some combination of any two previous terms. ''m'' is usually a power of 2 (''m'' = 2''M''), often 232 or 264. The operator denotes a general . This may be either addition, subtraction, multiplication, or the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudorandom Number Generator
A pseudorandom number generator (PRNG), also known as a deterministic random bit generator (DRBG), is an algorithm for generating a sequence of numbers whose properties approximate the properties of sequences of random numbers. The PRNG-generated sequence is not truly random, because it is completely determined by an initial value, called the PRNG's ''seed'' (which may include truly random values). Although sequences that are closer to truly random can be generated using hardware random number generators, ''pseudorandom number generators'' are important in practice for their speed in number generation and their reproducibility. PRNGs are central in applications such as simulations (e.g. for the Monte Carlo method), electronic games (e.g. for procedural generation), and cryptography. Cryptographic applications require the output not to be predictable from earlier outputs, and more elaborate algorithms, which do not inherit the linearity of simpler PRNGs, are needed. Good statist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diehard Tests
The diehard tests are a battery of statistical tests for measuring the quality of a random number generator. They were developed by George Marsaglia over several years and first published in 1995 on a CD-ROM of random numbers. Test overview ; Birthday spacings : Choose random points on a large interval. The spacings between the points should be asymptotically exponentially distributed. The name is based on the birthday paradox. ; Overlapping permutations : Analyze sequences of five consecutive random numbers. The 120 possible orderings should occur with statistically equal probability. ; Ranks of matrices : Select some number of bits from some number of random numbers to form a matrix over , then determine the rank of the matrix. Count the ranks. ; Monkey tests : Treat sequences of some number of bits as "words". Count the overlapping words in a stream. The number of "words" that do not appear should follow a known distribution. The name is based on the infinite monkey theorem. ; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VIC Cipher
Vic (; es, Vic or Pancracio Celdrán (2004). Diccionario de topónimos españoles y sus gentilicios (5ª edición). Madrid: Espasa Calpe. p. 843. ISBN 978-84-670-3054-9. «Vic o Vich (viquense, vigitano, vigatán, ausense, ausetano, ausonense): Ciudad barcelonesa, cabeza del partido judicial situada cerca de los ríos Ter y Méder, en la Plana de Vich.») is the capital of the ''comarca'' of Osona, in the province of Barcelona, Catalonia, Spain. Vic is located from Barcelona and from Girona. Geography Vic lies in the middle of the Plain of Vic, equidistant from Barcelona and the Pyrenees. Vic has persistent fog in winter as a result of a thermal inversion, with temperatures as low as -10 °C, an absolute record of -24 °C and episodes of cold and severe snowstorms. For this reason the natural vegetation includes the pubescent oak typical of the sub-Mediterranean climates of eastern France, Northern Italy and the Balkans. Names Originally known as ''Auso'', it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pike (cipher)
The Pike stream cipher was invented by Ross Anderson to be a "leaner and meaner" version of FISH after he broke FISH in 1994. Its name is supposed to be a humorous allusion to the pike fish. The cipher combines ideas from A5 with the lagged Fibonacci generators used in FISH. It is about 10% faster than FISH, yet believed to be much stronger. It potentially has a huge key length In cryptography, key size, key length, or key space refer to the number of bits in a key used by a cryptographic algorithm (such as a cipher). Key length defines the upper-bound on an algorithm's security (i.e. a logarithmic measure of the faste ..., and no attacks have been published . External links ''Ross Anderson, «On Fibonacci Keystream Generators»'' 1994. ''On Fibonacci Keystream Generators'' Ross Anderson, 27-Jul-2006. Stream ciphers {{crypto-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FISH (cipher)
The FISH (FIbonacci SHrinking) stream cipher is a fast software based stream cipher using Lagged Fibonacci generators, plus a concept from the shrinking generator cipher. It was published by Siemens Siemens AG ( ) is a German multinational conglomerate corporation and the largest industrial manufacturing company in Europe headquartered in Munich with branch offices abroad. The principal divisions of the corporation are ''Industry'', '' ... in 1993. FISH is quite fast in software and has a huge key length. However, in the same paper where he proposed Pike, Ross Anderson showed that FISH can be broken with just a few thousand bits of known plaintext. References *. *. Stream ciphers Fibonacci numbers {{Crypto-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xoroshiro128+
xoroshiro128+ (named after its operations: XOR, rotate, shift, rotate) is a pseudorandom number generator intended as a successor to xorshift+. Instead of perpetuating Marsaglia's tradition of xorshift as a basic operation, xoroshiro128+ uses a shift/rotate-based linear transformation designed by Sebastiano Vigna in collaboration with David Blackman. The result is a significant improvement in speed and statistical quality. Statistical Quality The lowest bits of the output generated by xoroshiro128+ have low quality. The authors of xoroshiro128+ acknowledge that it does not pass all statistical tests, stating This is xoroshiro128+ 1.0, our best and fastest small-state generator for floating-point numbers. We suggest to use its upper bits for floating-point generation, as it is slightly faster than xoroshiro128**. It passes all tests we are aware of except for the four lower bits, which might fail linearity tests (and just those), so if low linear complexity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACORN (PRNG)
The ACORN or ″Additive Congruential Random Number″ generators are a robust family of PRNGs (pseudorandom number generators) for sequences of uniformly distributed pseudo-random numbers, introduced in 1989 and still valid in 2019, thirty years later. Introduced by R.S.Wikramaratna,Wikramaratna, R.S. (1989). ACORN — A new method for generating sequences of uniformly distributed Pseudo-random Numbers. Journal of Computational Physics. 83. 16-31. ACORN was originally designed for use in geostatistical and geophysical Monte Carlo simulations, and later extended for use on parallel computers.R.S. Wikramaratna, Pseudo-random number generation for parallel processing — A splitting approach, SIAM News 33 (9) (2000). Over the ensuing decades, theoretical analysis (formal proof of convergence and statistical results), empirical testing (using standard test suites), and practical application work have continued, despite the appearance and promotion of other better-known ut not necess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Congruential Generator
A linear congruential generator (LCG) is an algorithm that yields a sequence of pseudo-randomized numbers calculated with a discontinuous piecewise linear equation. The method represents one of the oldest and best-known pseudorandom number generator algorithms. The theory behind them is relatively easy to understand, and they are easily implemented and fast, especially on computer hardware which can provide modular arithmetic by storage-bit truncation. The generator is defined by the recurrence relation: :X_ = \left( a X_n + c \right)\bmod m where X is the sequence of pseudo-random values, and : m,\, 0 |
List Of Random Number Generators
Random number generators are important in many kinds of technical applications, including physics, engineering or mathematical computer studies (e.g., Monte Carlo simulations), cryptography and gambling (on game servers). This list includes many common types, regardless of quality. Pseudorandom number generators (PRNGs) Whenever using a pseudorandom number generator, keep in mind John von Neumann's dictum "Anyone who considers arithmetical methods of producing random digits is, of course, in a state of sin." The following algorithms are pseudorandom number generators. Cryptographic algorithms Cipher algorithms and cryptographic hashes can be used as very high-quality pseudorandom number generators. However, generally they are considerably slower (typically by a factor 2-10) than fast, non-cryptographic random number generators. These include: * Stream ciphers. Popular choices are Salsa20 or ChaCha (often with the number of rounds reduced to 8 for speed), ISAAC, HC-128 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oracle Database
Oracle Database (commonly referred to as Oracle DBMS, Oracle Autonomous Database, or simply as Oracle) is a multi-model database management system produced and marketed by Oracle Corporation. It is a database commonly used for running online transaction processing (OLTP), data warehousing (DW) and mixed (OLTP & DW) database workloads. Oracle Database is available by several service providers on-prem, on-cloud, or as a hybrid cloud installation. It may be run on third party servers as well as on Oracle hardware (Exadata on-prem, on Oracle Cloud or at Cloud at Customer). History Larry Ellison and his two friends and former co-workers, Bob Miner and Ed Oates, started a consultancy called Software Development Laboratories (SDL) in 1977. SDL developed the original version of the Oracle software. The name ''Oracle'' comes from the code-name of a CIA-funded project Ellison had worked on while formerly employed by Ampex. Releases and versions Oracle products follow a custom r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C++11
C++11 is a version of the ISO/IEC 14882 standard for the C++ programming language. C++11 replaced the prior version of the C++ standard, called C++03, and was later replaced by C++14. The name follows the tradition of naming language versions by the publication year of the specification, though it was formerly named ''C++0x'' because it was expected to be published before 2010. Although one of the design goals was to prefer changes to the libraries over changes to the core language, C++11 does make several additions to the core language. Areas of the core language that were significantly improved include multithreading support, generic programming support, uniform initialization, and performance. Significant changes were also made to the C++ Standard Library, incorporating most of the C++ Technical Report 1 (TR1) libraries, except the library of mathematical special functions. C++11 was published as ''ISO/IEC 14882:2011'' in September 2011 and is available for a fee. The worki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtract With Carry
Subtract-with-carry is a pseudorandom number generator: one of many algorithms designed to produce a long series of random-looking numbers based on a small amount of starting data. It is of the lagged Fibonacci type introduced by George Marsaglia and Arif Zaman in 1991.A New Class of Random Number Generators George Marsaglia and Arif Zaman, The Annals of Applied Probability, Vol. 1, No. 3, 1991 "Lagged Fibonacci" refers to the fact that each random number is a function of two of the preceding numbers at some specified, fixed offsets, or "lags". Algorithm Sequence generated by the subtract-with-carry engine may be described by the |
