localsearch 0.24.0

A Library of Local Search based Metaheuristics
Documentation 
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use std::collections::VecDeque;

/// Sliding window based acceptance counter
#[derive(Debug, Clone)]
pub struct AcceptanceCounter {
    window_size: usize,
    buffer: std::collections::VecDeque<u8>,
    n_accepted: usize,
}

impl Default for AcceptanceCounter {
    fn default() -> Self {
        Self::new(100)
    }
}

impl AcceptanceCounter {
    /// Constructor of AcceptanceCounter
    /// - `window_size` : size of the sliding window
    pub fn new(window_size: usize) -> Self {
        Self {
            window_size,
            buffer: VecDeque::with_capacity(window_size),
            n_accepted: 0,
        }
    }

    /// Update the counter with a new result
    pub fn enqueue(&mut self, accepted: bool) {
        if self.buffer.len() == self.window_size {
            let old = self.buffer.pop_front().unwrap();
            self.n_accepted -= old as usize;
        }
        let value = accepted as u8;
        self.buffer.push_back(value);
        self.n_accepted += value as usize;
    }

    /// Get the acceptance ratio
    pub fn acceptance_ratio(&self) -> f64 {
        let total = self.buffer.len();
        if total == 0 {
            0.0
        } else {
            self.n_accepted as f64 / total as f64
        }
    }
}