From f18d7b41a29d117ad28e6f687175d71f777eb986 Mon Sep 17 00:00:00 2001
From: Simon Gardling <titaniumtown@gmail.com>
Date: Mon, 7 Mar 2022 15:36:40 -0500
Subject: [PATCH] fixes

---
 src/egui_app.rs |  6 ++++--
 src/function.rs | 29 ++++++++++-------------------
 src/parsing.rs  | 19 +++++++------------
 3 files changed, 21 insertions(+), 33 deletions(-)

diff --git a/src/egui_app.rs b/src/egui_app.rs
index d67489b..7eb900e 100644
--- a/src/egui_app.rs
+++ b/src/egui_app.rs
@@ -269,6 +269,10 @@ impl MathApp {
                     let proc_func_str = add_asterisks(self.func_strs[i].clone());
                     if (proc_func_str != function.get_func_str())
                         | self.last_error.iter().any(|ele| ele.0 == i)
+                        | integral_toggle
+                        | derivative_toggle
+                        | max_x_changed
+                        | min_x_changed
                     {
                         // let proc_func_str = self.func_strs[i].clone();
                         let func_test_output = test_func(&proc_func_str);
@@ -299,8 +303,6 @@ impl MathApp {
                                 .map(|(a, b)| (*a, b.clone()))
                                 .collect();
                         }
-                    } else {
-                        function.empty_func_str();
                     }
                 }
 
diff --git a/src/function.rs b/src/function.rs
index 01efc45..c2e261a 100644
--- a/src/function.rs
+++ b/src/function.rs
@@ -35,7 +35,6 @@ pub struct FunctionEntry {
 
     pub(crate) integral: bool,
     pub(crate) derivative: bool,
-    pub(crate) nth_derivative: u64,
     integral_min_x: f64,
     integral_max_x: f64,
     integral_num: usize,
@@ -56,7 +55,6 @@ impl FunctionEntry {
             derivative_cache: None,
             integral: false,
             derivative: false,
-            nth_derivative: 1,
             integral_min_x: f64::NAN,
             integral_max_x: f64::NAN,
             integral_num: 0,
@@ -64,9 +62,6 @@ impl FunctionEntry {
         }
     }
 
-    // Runs the internal function to get values
-    fn run_func(&self, x: f64) -> f64 { self.function.get(x) }
-
     pub fn update(
         &mut self, func_str: String, integral: bool, derivative: bool, integral_min_x: Option<f64>,
         integral_max_x: Option<f64>, integral_num: Option<usize>, sum: Option<RiemannSum>,
@@ -122,7 +117,7 @@ impl FunctionEntry {
                         if let Some(i) = x_data.get_index(x) {
                             back_cache[i]
                         } else {
-                            Value::new(x, self.run_func(x))
+                            Value::new(x, self.function.get(x))
                         }
                     })
                     .collect(),
@@ -138,7 +133,7 @@ impl FunctionEntry {
                             if let Some(i) = x_data.get_index(x) {
                                 derivative_cache[i]
                             } else {
-                                Value::new(x, self.function.derivative(x, self.nth_derivative))
+                                Value::new(x, self.function.derivative(x))
                             }
                         })
                         .collect(),
@@ -166,7 +161,7 @@ impl FunctionEntry {
                 self.back_cache = Some(
                     (0..self.pixel_width)
                         .map(|x| (x as f64 / resolution as f64) + self.min_x)
-                        .map(|x| Value::new(x, self.run_func(x)))
+                        .map(|x| Value::new(x, self.function.get(x)))
                         .collect(),
                 );
             }
@@ -180,9 +175,7 @@ impl FunctionEntry {
                     self.derivative_cache = Some(
                         (0..self.pixel_width)
                             .map(|x| (x as f64 / resolution as f64) + self.min_x)
-                            .map(|x| {
-                                Value::new(x, self.function.derivative(x, self.nth_derivative))
-                            })
+                            .map(|x| Value::new(x, self.function.derivative(x)))
                             .collect(),
                     );
                 }
@@ -253,9 +246,11 @@ impl FunctionEntry {
                 };
 
                 let y = match self.sum {
-                    RiemannSum::Left => self.run_func(left_x),
-                    RiemannSum::Right => self.run_func(right_x),
-                    RiemannSum::Middle => (self.run_func(left_x) + self.run_func(right_x)) / 2.0,
+                    RiemannSum::Left => self.function.get(left_x),
+                    RiemannSum::Right => self.function.get(right_x),
+                    RiemannSum::Middle => {
+                        (self.function.get(left_x) + self.function.get(right_x)) / 2.0
+                    }
                 };
 
                 if last_positive.is_none() {
@@ -276,7 +271,7 @@ impl FunctionEntry {
     // Set func_str to an empty string
     pub fn empty_func_str(&mut self) { self.func_str = String::new(); }
 
-    pub fn get_func_str(&self) -> String { self.func_str.clone() }
+    pub fn get_func_str(&self) -> &str { &self.func_str }
 
     // Updates riemann value and invalidates front_cache if needed
     pub fn update_riemann(mut self, riemann: RiemannSum) -> Self {
@@ -315,10 +310,6 @@ impl FunctionEntry {
         self.integral_max_x = max_x;
         self
     }
-
-    // Invalidates the derivative cache. This would be used in the case of a change in the nth_derivative
-    #[allow(dead_code)]
-    pub fn invalidate_derivative_cache(&mut self) { self.derivative_cache = None; }
 }
 
 #[test]
diff --git a/src/parsing.rs b/src/parsing.rs
index 0ac0632..3154157 100644
--- a/src/parsing.rs
+++ b/src/parsing.rs
@@ -8,23 +8,18 @@ pub struct BackingFunction {
 impl BackingFunction {
     pub fn new(func_str: &str) -> Self {
         let function = exmex::parse::<f64>(func_str).unwrap();
+        let derivative = function.partial(0).unwrap_or(function.clone());
+        println!("{}\n{}", function.unparse(), derivative.unparse());
+
         Self {
-            function: function.clone(),
-            derivative: function.partial(0).unwrap(),
+            function,
+            derivative,
         }
     }
 
     pub fn get(&self, x: f64) -> f64 { self.function.eval(&[x]).unwrap_or(f64::NAN) }
 
-    pub fn derivative(&self, x: f64, n: u64) -> f64 {
-        if n == 0 {
-            self.get(x)
-        } else if n == 1 {
-            self.derivative.eval(&[x]).unwrap_or(f64::NAN)
-        } else {
-            panic!("n > 1");
-        }
-    }
+    pub fn derivative(&self, x: f64) -> f64 { self.derivative.eval(&[x]).unwrap_or(f64::NAN) }
 }
 
 /*
@@ -95,7 +90,7 @@ pub fn add_asterisks(function_in: String) -> String {
         output_string += &c.to_string();
     }
 
-    output_string.replace('π', "pi") // π -> pi
+    output_string
 }
 
 // Tests function to make sure it's able to be parsed. Returns the string of the Error produced, or an empty string if it runs successfully.