#![feature(external_doc)]
use ta_common::fixed_queue::FixedQueue;
use ta_common::traits::Indicator;
#[doc(include = "../README.md")]
pub struct SMA {
accumulator: f64,
period: u32,
history: FixedQueue<f64>,
}
impl SMA {
pub fn new(period: u32) -> SMA {
Self {
accumulator: 0_f64,
period,
history: FixedQueue::new(period),
}
}
pub fn get_total(&self) -> f64 {
return self.accumulator;
}
}
impl Indicator<f64, Option<f64>> for SMA {
fn next(&mut self, input: f64) -> Option<f64> {
if self.history.is_full() {
let out = self.history.at(0).unwrap();
self.history.add(input);
self.accumulator = self.accumulator - out + input;
} else {
self.history.add(input);
self.accumulator = self.accumulator + input;
}
if self.history.is_full() {
return Some(self.accumulator/self.period as f64);
}
None
}
fn reset(&mut self) {
self.history.clear();
self.accumulator = 0_f64;
}
}
#[cfg(test)]
mod tests {
use crate::SMA;
use ta_common::traits::Indicator;
#[test]
fn it_works() {
let mut sma = SMA::new(5);
assert_eq!(sma.next(81.59), None);
assert_eq!(sma.next(81.06), None);
assert_eq!(sma.next(82.87), None);
assert_eq!(sma.next(83.00), None);
assert_eq!(sma.next(83.61), Some(82.426));
assert_eq!(sma.next(83.15), Some(82.73799999999999));
assert_eq!(sma.next(82.84), Some(83.09399999999998));
assert_eq!(sma.next(83.99), Some(83.31799999999998));
assert_eq!(sma.next(84.55), Some(83.62799999999999));
assert_eq!(sma.next(84.36), Some(83.77799999999999));
assert_eq!(sma.next(85.53), Some(84.25399999999998));
assert_eq!(sma.next(86.54), Some(84.99399999999997));
assert_eq!(sma.next(86.89), Some(85.57399999999997));
assert_eq!(sma.next(87.77), Some(86.21799999999996));
assert_eq!(sma.next(87.29), Some(86.80399999999996));
}
}