Function nois::pick

pub fn pick<T>(randomness: [u8; 32], n: usize, data: Vec<T>) -> Vec<T>

Picks n elements from a given list.

This consumes the vector of elements for efficientcy reasons. Applications that do not need the original data anymore benefit from an efficient in-place implementation.

Examples

Pick 6 out of 49:

use nois::{randomness_from_str, pick};

let randomness = randomness_from_str("9e8e26615f51552aa3b18b6f0bcf0dae5afbe30321e8d7ea7fa51ebeb1d8fe62").unwrap();

// We are randomly shuffling a vector of integers [1,2,3,4]
let data = vec![
  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
  12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
  23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,
  34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44,
  45, 46, 47, 48, 49
];
let picked = pick(randomness, 6, data);
// The length of the vector is the same but the order of the elements has changed
assert_eq!(picked.len(), 6);
assert_eq!(picked, vec![7, 33, 18, 22, 8, 10]);

Pick two winners from a vector of strings:

use nois::{randomness_from_str, pick};

let randomness = randomness_from_str("9e8e26615f51552aa3b18b6f0bcf0dae5afbe30321e8d7ea7fa51ebeb1d8fe62").unwrap();

let data = vec!["bob".to_string(), "mary".to_string(), "su".to_string(), "marc".to_string()];
let picked = pick(randomness, 2, data);
// The length of the vector is the same but the order of the elements has changed
assert_eq!(picked.len(), 2);
assert_eq!(picked, vec!["su".to_string(), "bob".to_string()]);