use std::cmp::Ordering;
use std::f64::NAN;
pub struct Dataset {
values: Vec<f64>,
sum: f64,
sorted: bool,
}
fn cmp_f64(a: &f64, b: &f64) -> Ordering {
assert!(!a.is_nan() && !b.is_nan());
if a < b {
return Ordering::Less;
} else if a > b {
return Ordering::Greater;
} else {
return Ordering::Equal;
}
}
impl Dataset {
pub fn new() -> Self {
Dataset {
values: Vec::new(),
sum: 0.0,
sorted: false,
}
}
pub fn add(&mut self, value: f64) {
self.values.push(value);
self.sum += value;
self.sorted = false;
}
pub fn lower_quantile(&mut self, q: f64) -> f64 {
if q < 0.0 || q > 1.0 || self.values.len() == 0 {
return NAN;
}
self.sort();
let rank = q * (self.values.len() - 1) as f64;
self.values[rank.floor() as usize]
}
pub fn upper_quantile(&mut self, q: f64) -> f64 {
if q < 0.0 || q > 1.0 || self.values.len() == 0 {
return NAN;
}
self.sort();
let rank = q * (self.values.len() - 1) as f64;
self.values[rank.ceil() as usize]
}
pub fn min(&mut self) -> f64 {
self.sort();
self.values[0]
}
pub fn max(&mut self) -> f64 {
self.sort();
self.values[self.values.len() - 1]
}
pub fn sum(&self) -> f64 {
self.sum
}
pub fn count(&self) -> usize {
self.values.len()
}
fn sort(&mut self) {
if self.sorted {
return;
}
self.values.sort_by(cmp_f64);
self.sorted = true;
}
}