Function malachite_base::sets::random::random_b_tree_sets_min_length

pub fn random_b_tree_sets_min_length<I: Iterator>(
    seed: Seed, 
    min_length: u64, 
    xs_gen: &dyn Fn(Seed) -> I, 
    mean_length_numerator: u64, 
    mean_length_denominator: u64
) -> RandomBTreeSets<I::Item, GeometricRandomNaturalValues<u64>, I> where
    I::Item: Ord, 

Generates random BTreeSets with a minimum length, using elements from an iterator.

Strictly speaking, the input iterator must generate infinitely many distinct elements. In practice it only needs to generate $k$ distinct elements, where $k$ is the largest length actually sampled from the geometric distribution. For example, if mean_length_numerator / mean_length_denominator is significantly lower than 256, then it’s ok to use random_unsigneds::<u8>.

$$ P((x_i)_{i=0}^{n-1}) = n!P_g(n)\prod_{i=0}^{n-1}P(x_i), $$ where $P_g(n)$ is the probability function described in geometric_random_unsigned_inclusive_range, with $a$ equal to min_length and b to u64::MAX.

xs_gen must be infinite.

Panics

Panics if mean_length_numerator or mean_length_denominator are zero, if their ratio is less than or equal to min_length, or if they are too large and manipulating them leads to arithmetic overflow.

Examples

extern crate itertools;
#[macro_use]
extern crate maplit;

use itertools::Itertools;
use malachite_base::num::random::random_primitive_ints;
use malachite_base::random::EXAMPLE_SEED;
use malachite_base::sets::random::random_b_tree_sets_min_length;

fn main() {
    let xs = random_b_tree_sets_min_length(
        EXAMPLE_SEED,
        2,
        &random_primitive_ints::<u8>,
        6,
        1
    );
    let values = xs.take(20).collect_vec();
    assert_eq!(
        values,
        &[
            btreeset!{11, 85},
            btreeset!{
                30, 32, 38, 90, 134, 136, 162, 166, 177, 200, 203, 217, 218, 223, 234, 235
            },
            btreeset!{9, 106, 151, 204, 213, 216},
            btreeset!{39, 78, 91, 97, 191, 253},
            btreeset!{170, 175, 232},
            btreeset!{2, 233},
            btreeset!{17, 22, 32, 35, 114, 198, 217},
            btreeset!{65, 114, 121, 173},
            btreeset!{25, 79, 144, 148, 173, 222},
            btreeset!{52, 115},
            btreeset!{34, 69, 73, 91, 112, 137, 153, 178},
            btreeset!{95, 106},
            btreeset!{167, 197},
            btreeset!{74, 86, 101, 115, 122, 130, 150, 168, 172, 177, 207, 218, 221},
            btreeset!{9, 48, 52, 109, 123, 133, 159, 201, 247, 250},
            btreeset!{196, 235},
            btreeset!{40, 68, 97, 104, 190},
            btreeset!{7, 216},
            btreeset!{11, 24, 43, 112, 157, 216, 217},
            btreeset!{29, 51, 55, 65, 84, 89, 103, 135, 191, 206, 211}
        ]
    );
}