A basic random number generator implementing the linear congruential generator algorithm, which is faster but less random than the default random source.
- iOS 9.0+
- macOS 10.11+
- tvOS 9.0+
To generate basic random values with this random source, use the methods defined in the
GKRandom protocol. To generate random values with a specific range and distribution, use this random source with the
GKRandom class or one of its subclasses.
When you create an instance of this class, the resulting random source is both independent and deterministic—that is, the sequence of numbers generated by one instance has no effect on the sequence generated by any other instance, and that sequence can be replicated when necessary. For details on replicating sequences, see the
seed property and
The linear congruential random source uses the algorithm described by Donald E. Knuth in The Art of Computer Programming, Volume 2: Seminumerical Algorithms, section 3.2.1, with the common seed mask value of
0x5DEECE66D. This random source is therefore compatible with other implementations of that algorithm, including the
java class in Java. That is, if you initialize a
GKLinear instance and a compatible implementation using the same seed value, both generate the same sequence of numbers.