rand_simple/distributions/
uniform.rs

1use crate::standard_distributions::{generate_random_state, xorshift160_0_to_1};
2
3/// Uniform distribution
4/// # Example
5/// ```
6/// let mut uniform = rand_simple::Uniform::new(1192_u32);
7/// assert_eq!(format!("{uniform}"), "Range (Closed Interval): [0, 1]");
8/// println!("Returns a random number -> {}", uniform.sample());
9///
10/// // When changing the parameters of the random variable
11/// let min: f64 = -1_f64;
12/// let max: f64 = 1_f64;
13/// let result: Result<(f64, f64), &str> = uniform.try_set_params(min, max);
14/// assert_eq!(format!("{uniform}"), "Range (Closed Interval): [-1, 1]");
15/// println!("Returns a random number -> {}", uniform.sample());
16/// ```
17pub struct Uniform {
18    xyzuv: [u32; 5], // 状態変数
19    min: f64,        // 最小値
20    max: f64,        // 最大値
21}
22
23impl Uniform {
24    /// Constructor
25    /// * `_seed` - The seed for the random number generator
26    pub fn new(_seed: u32) -> Self {
27        Self {
28            xyzuv: generate_random_state(_seed),
29            min: 0_f64,
30            max: 1_f64,
31        }
32    }
33
34    /// Calculate a random number.
35    /// # Returns
36    /// A random floating-point number within the specified range.
37    pub fn sample(&mut self) -> f64 {
38        xorshift160_0_to_1(&mut self.xyzuv) * (self.max - self.min) + self.min
39    }
40
41    /// Attempt to modify the parameters of the random variable.
42    /// * `min` - Minimum value
43    /// * `max` - Maximum value
44    pub fn try_set_params(&mut self, min: f64, max: f64) -> Result<(f64, f64), &'static str> {
45        if min >= max {
46            Err("The minimum and maximum values are equal or the minimum value is greater. The parameters of the random variable will remain unchanged.")
47        } else {
48            self.min = min;
49            self.max = max;
50            Ok((self.min, self.max))
51        }
52    }
53}
54
55impl core::fmt::Display for Uniform {
56    /// Formatter for displaying with println! macro and others.
57    /// * Range (Closed Interval)
58    fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
59        write!(f, "Range (Closed Interval): [{}, {}]", self.min, self.max)?;
60        Ok(())
61    }
62}
rand_simple/distributions/uniform.rs

rand_simple/distributions/
uniform.rs
