@rnd_gamma(α:float)

returns a random generator that produces floating-point values according to a gamma distribution P:

   P(x | α) = x^(α-1) / Γ(α),    x ≥ 0.

See @rnd_bernoulli for a description of random generators.

See also Random Generators @rand,    @rand_int,    @random,    @rnd_bernoulli,    @rnd_binomial,    @rnd_exponential,    @rnd_gamma,    @rnd_geometric,    @rnd_normal,    @rnd_uniform_float,    @rnd_uniform_int