This is an old version, view current version.
11.6 Pseudorandom number generators
For most of the probability functions, there is a matching
pseudorandom number generator (PRNG) with the suffix _rng
. For
example, the function normal_rng(real, real)
accepts two real
arguments, an unconstrained location \(\mu\) and positive scale \(\sigma > 0\), and returns an unconstrained pseudorandom value drawn from
\(\text{Normal}(\mu,\sigma)\). There are also vectorized forms of
random number generators which return more than one random variate at
a time.
11.6.1 Restricted to transformed data and generated quantities
Unlike regular functions, the PRNG functions may only be used in the transformed data or generated quantities blocks.
11.6.2 Limited vectorization
Unlike the probability functions, only some of the PRNG functions are vectorized.