Move function currying to Spline class

src/lib.rs

@@ -82,13 +82,13 @@ impl MonotonicCubicSpline {
                 slopes[i] = 0.0;
                 slopes[i + 1] = 0.0;
             } else {
-                let a = slopes[i] / secants[i];
-                let b = slopes[i + 1] / secants[i];
-                let h = a.hypot(b);
+                let alpha = slopes[i] / secants[i];
+                let beta = slopes[i + 1] / secants[i];
+                let h = alpha.hypot(beta);
                 if h > 9.0 {
                     let t = 3.0 / h;
-                    slopes[i] = t * a * secants[i];
-                    slopes[i + 1] = t * b * secants[i];
+                    slopes[i] = t * alpha * secants[i];
+                    slopes[i + 1] = t * beta * secants[i];
                 }
             }
         }
@@ -132,6 +132,13 @@ impl MonotonicCubicSpline {
                                              (*self.m_m.get(i).unwrap(), *self.m_m.get(i+1).unwrap()));
     }
 
+    fn curry(x: Vec<f64>, y: Vec<f64>) -> impl Fn(f64) -> f64 {
+        move |p| {
+            let mut spline = MonotonicCubicSpline::new(&x, &y);
+            spline.interpolate(p)
+        }
+    }
+
 }
 
 #[cfg(test)]
@@ -163,6 +170,7 @@ mod test_normal {
         assert_delta!(0.3989423, _pdf, 1e-5);
     }
 
+
     #[test]
     fn interpolation() {
         use matplotrust::*;
@@ -170,14 +178,14 @@ mod test_normal {
         let x = vec![0.0, 2.0, 3.0, 10.0];
         let y = vec![1.0, 4.0, 8.0, 10.5];
 
-        let mut spline = MonotonicCubicSpline::new(&x, &y);
+        let smooth = MonotonicCubicSpline::curry(x.clone(), y.clone());
 
         let mut x_interp = Vec::new();
         let mut y_interp = Vec::new();
         for i in 0..100 {
             let p = i as f64 / 10.0;
             x_interp.push(p);
-            y_interp.push(spline.interpolate(p));
+            y_interp.push(smooth(p));
         }
         let mut figure = Figure::new();
         let points = scatter_plot::<f64, f64>(x, y, None);