Interface to the OS number rg.¶
`
Older versios of YAP supported random number access through the expression X is random. Inspired by SWI-Prolog, the newer code supports:
-
initialization;
-
random numbers as integers (signed or absolute) or as floating points;
-
cryptographic quality random numbers
By default YAP uses random, the pseudo-random number generator. Use the prolog flag random_number_generator if you prefer random or rand. Use arc4random for higher quality random numbers, that do not have a seed.
Functions:¶
1. UInt Yap_unsigned_integer_random(void):
1. Int Yap_signed_integer_random(void):
1. static Int Yap_integer_in_range(uint64_t min, uint64_t max):
1. static Int Yap_double_in_range(double min, double max):
1. static Int Srandom(USES_REGS1): : "srandom(Seed" )
@class srandom_1
Set the Seed for the pseudo random generator.
1. static Int URandom(USES_REGS1): : "random(-Positive_Integer" )
@class random_1
Unify the first argument with an unsigned pseudo-random integer.
1. static Int rando/3(USES_REGS1): : "random(+Min,+Max,-R" )
@class random_3
Unify the third argument with an pseudo-random number in the interval [Min-Max[. If both Min and Max are integers, R will also be an integer, otherwise _R will be a floating point number.
1. static Int Random(USES_REGS1): : "signed_random(-Integer" )
@class signed_random_1
Unify the first argument with an pseudo-random integer.
1. void Yap_InitRandom(void): : Initialize the default random number generator.
uses the process's srand call.