formula run

src/formula.rs

@@ -0,0 +1,20 @@
+use crate::node::Node;
+
+#[derive(Clone)]
+pub struct Formula {
+    tree: Node,
+    x: f64,
+    rating: f64,
+}
+
+impl Formula {
+    pub fn run(&mut self, inputs: Vec<f64>) -> Vec<f64> {
+        let mut outputs: Vec<f64> = vec![];
+        for input in inputs {
+            self.x = input;
+            outputs.push(self.tree.get_value());
+        }
+        outputs
+    }
+    pub fn mutate(&mut self) {}
+}

src/lib.rs

@@ -1 +1,2 @@
+mod formula;
 mod node;

src/node/handler.rs

@@ -1,7 +1,9 @@
+#[derive(Clone, Copy)]
 pub enum NodeHandler {
     Number { number: f64 },
     Function { function: fn(Vec<f64>) -> f64 },
     Variable { getter: fn() -> f64 },
+    Empty,
 }
 
 impl NodeHandler {
@@ -10,6 +12,7 @@ impl NodeHandler {
             NodeHandler::Number { number } => number.clone(),
             NodeHandler::Function { function } => function(inputs),
             NodeHandler::Variable { getter } => getter(),
+            NodeHandler::Empty => 0f64,
         }
     }
 }

src/node/mod.rs

@@ -5,6 +5,7 @@ mod functions;
 mod handler;
 mod node_modifier;
 
+#[derive(Clone)]
 pub struct Node {
     children: Vec<Node>,
     handler: NodeHandler,