Begin working on batch.

src/gaussian.rs

@@ -40,11 +40,8 @@ impl Gaussian {
         self.sigma.powi(-2)
     }
 
-    pub fn forget(&self, gamma: f64, t: u32) -> Self {
-        Self::new(
-            self.mu,
-            (self.sigma().powi(2) + t as f64 * gamma.powi(2)).sqrt(),
-        )
+    pub fn forget(&self, gamma: f64, t: f64) -> Self {
+        Self::new(self.mu, (self.sigma().powi(2) + t * gamma.powi(2)).sqrt())
     }
 
     pub fn delta(&self, m: Gaussian) -> (f64, f64) {