Random

Random provides an interface to Ruby’s pseudo-random number generator, or PRNG. The PRNG produces a deterministic sequence of bits which approximate true randomness. The sequence may be represented by integers, floats, or binary strings.

The generator may be initialized with either a system-generated or user-supplied seed value by using Random.srand.

The class method Random.rand provides the base functionality of Kernel.rand along with better handling of floating point values. These are both interfaces to Random::DEFAULT, the Ruby system PRNG.

Random.new will create a new PRNG with a state independent of Random::DEFAULT, allowing multiple generators with different seed values or sequence positions to exist simultaneously. Random objects can be marshaled, allowing sequences to be saved and resumed.

PRNGs are currently implemented as a modified Mersenne Twister with a period of 2**19937-1.