Support more types

stats/src/stats.rs

@@ -0,0 +1,52 @@
+use std::time::{Duration, Instant};
+
+pub struct EMA {
+    ema: f32,
+    emv: f32,
+    k: f32,
+}
+
+impl EMA {
+    pub fn default() -> Self {
+        Self {
+            ema: 0.0,
+            emv: 0.0,
+            k: 0.05,
+        }
+    }
+
+    pub fn update<V>(&mut self, v: V)
+    where
+        V: Into<f32>,
+    {
+        let k = self.k;
+        let dv = v.into() - self.ema;
+        self.ema += k * dv;
+        self.emv = (1f32 - k) * (self.emv + k * dv * dv);
+    }
+}
+
+pub struct CheckEvery {
+    ts_last: Instant,
+    dt: Duration,
+}
+
+impl CheckEvery {
+    pub fn new(dt: Duration) -> Self {
+        Self {
+            ts_last: Instant::now(),
+            dt,
+        }
+    }
+
+    pub fn is_elapsed_now(&mut self) -> f32 {
+        let now = Instant::now();
+        let dt = now.duration_since(self.ts_last);
+        if dt >= self.dt {
+            self.ts_last = now;
+            dt.as_secs_f32()
+        } else {
+            -16f32
+        }
+    }
+}