uniform, a C++ code which returns a sequence of uniformly distributed pseudorandom numbers.

The fundamental underlying random number generator is based on a simple, old, and limited linear congruential random number generator originally used in the IBM System 360. If you want state of the art random number generation, look elsewhere!

The C++ math library already has random number functions, and it is not the purpose of UNIFORM to replace or improve them.

Rather, this library makes it possible to compare certain computations that use uniform random numbers, written in C, C++, FORTRAN77, FORTRAN90, Mathematica, MATLAB, or Python.

Various types of random data can be computed. The routine names are chosen to indicate the corresponding type:

In some cases, a one dimension vector or two dimensional array of values is to be generated, and part of the name will therefore include:

The underlying random numbers are generally defined over some unit interval or region. Routines are available which return these "unit" values, while other routines allow the user to specify limits between which the unit values are rescaled. The name of a routine will usually include a tag suggestig which is the case:

The random number generator embodied here is not very sophisticated. It will not have the best properties of distribution, noncorrelation and long period. It is not the purpose of this library to achieve such worthy goals. This is simply a reasonably portable library that can be implemented in various languages, on various machines, and for which it is possible, for instance, to regard the output as a function of the seed, and moreover, to work directly with the sequence of seeds, if necessary.


The computer code and data files described and made available on this web page are distributed under the MIT license


uniform is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Data and Programs:

ASA183, a C++ code which implements the Wichman-Hill random number generator (RNG).

BOX_BEHNKEN, a C++ code which computes a Box-Behnken design, that is, a set of arguments to sample the behavior of a function of multiple parameters;

cpp_random_test, C++ codes which illustrate the use of the C++ random number generator routines.

FAURE, a C++ code which computes elements of a Faure quasirandom sequence.

HALTON, a C++ code which computes elements of a Halton Quasi Monte Carlo (QMC) sequence, using a simple interface.

HAMMERSLEY, a C++ code which computes elements of a Hammersley Quasi Monte Carlo (QMC) sequence, using a simple interface.

NIEDERREITER2, a C++ code which computes elements of a Niederreiter sequence using base 2.

NORMAL, a C++ code which computes elements of a sequence of pseudorandom normally distributed values.

RANDLC, a C++ code which generates a sequence of pseudorandom numbers, used by the NAS Benchmark programs.

RANDOM_SORTED, a C++ code which generates vectors of random values which are already sorted.

RANLIB, a C++ code which produces random samples from Probability Density Functions (PDF's), including Beta, Chi-square Exponential, F, Gamma, Multivariate normal, Noncentral chi-square, Noncentral F, Univariate normal, random permutations, Real uniform, Binomial, Negative Binomial, Multinomial, Poisson and Integer uniform, by Barry Brown and James Lovato.

RNGLIB, a C++ code which implements a random number generator (RNG) with splitting facilities, allowing multiple independent streams to be computed, by L'Ecuyer and Cote.

SOBOL, a C++ code which computes elements of a Sobol quasirandom sequence.


VAN_DER_CORPUT, a C++ code which computes elements of a 1D van der Corput sequence.


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    Parallel Programming: Techniques and Applications Using Networked Workstations and Parallel Computers,
    Prentice Hall,
    ISBN: 0-13-140563-2,
    LC: QA76.642.W54.

Source Code:

Last revised on 10 April 2020.