[det]getrand(-State)Query/set the state of the random generator. This is intended for
restarting the generator at a known state only. The predicate setrand/1
accepts an opaque term returned by
getrand/1. This term
may be asserted, written and read. The application may not make other
assumptions about this term.
For compatibility reasons with older versions of this library,
setrand/1 also accepts
rand(A,B,C), where A, B and C are integers in the
range 1..30,000. This argument is used to seed the random generator.
existence_error(random_state, _) is raised if the
underlying infrastructure cannot fetch the random state. This is
currently the case if SWI-Prolog is not compiled with the GMP library.
- See also
- set_random/1 and random_property/1
provide the SWI-Prolog native implementation.