Code improvements and better handling of empty integrals

src/egui_app.rs

@@ -1,5 +1,5 @@
 use crate::function::{FunctionEntry, RiemannSum, DEFAULT_FUNCTION_ENTRY};
-use crate::misc::{JsonFileOutput, SerdeValueHelper};
+use crate::misc::{option_vec_printer, JsonFileOutput, SerdeValueHelper};
 use crate::parsing::{process_func_str, test_func};
 
 use const_format::formatc;
@@ -329,7 +329,7 @@ pub struct MathApp {
 
 	/// Contains the list of Areas calculated (the vector of f64) and time it
 	/// took for the last frame (the Duration). Stored in a Tuple.
-	last_info: (Vec<f64>, Duration),
+	last_info: (Vec<Option<f64>>, Duration),
 
 	/// Stores settings (pretty self-explanatory)
 	settings: AppSettings,
@@ -341,7 +341,7 @@ impl Default for MathApp {
 			functions: vec![DEFAULT_FUNCTION_ENTRY.clone()],
 			func_strs: vec![String::new()],
 			last_error: Vec::new(),
-			last_info: (vec![0.0], Duration::ZERO),
+			last_info: (vec![None], Duration::ZERO),
 			settings: AppSettings::default(),
 		}
 	}
@@ -617,8 +617,9 @@ impl epi::App for MathApp {
 
 				// Display Area and time of last frame
 				ui.label(format!(
-					"Area: {:?} Took: {:?}",
-					self.last_info.0, self.last_info.1
+					"Area: {} Took: {:?}",
+					option_vec_printer(self.last_info.0.clone()),
+					self.last_info.1
 				));
 			});
 		});
@@ -668,8 +669,9 @@ impl epi::App for MathApp {
 			self.side_panel(ctx);
 		}
 
-		let mut area_list: Vec<f64> = Vec::new(); // Referenced in plotting code, but needs to be here so it can be later
-										  // referenced when storing `last_info`
+		// Referenced in plotting code, but needs to be here so it can be later
+		// referenced when storing `last_info`
+		let mut area_list: Vec<Option<f64>> = Vec::new();
 
 		// Central panel which contains the central plot (or an error created when
 		// parsing)
@@ -708,7 +710,7 @@ impl epi::App for MathApp {
 						.enumerate()
 						.map(|(i, function)| {
 							if self.func_strs[i].is_empty() {
-								return f64::NAN;
+								return None;
 							}
 
 							function.display(

src/function.rs

@@ -166,7 +166,7 @@ impl FunctionEntry {
 	pub fn display(
 		&mut self, plot_ui: &mut PlotUi, min_x: f64, max_x: f64, pixel_width: usize,
 		width_changed: bool, settings: AppSettings,
-	) -> f64 {
+	) -> Option<f64> {
 		let resolution: f64 = pixel_width as f64 / (max_x.abs() + min_x.abs());
 		let resolution_iter = resolution_helper(pixel_width + 1, min_x, resolution);
 
@@ -342,9 +342,9 @@ impl FunctionEntry {
 			);
 
 			// return value rounded to 8 decimal places
-			crate::misc::decimal_round(integral_data.1, 8)
+			Some(crate::misc::decimal_round(integral_data.1, 8))
 		} else {
-			f64::NAN // return NaN if integrals are disabled
+			None
 		}
 	}
 }

src/misc.rs

@@ -229,6 +229,35 @@ fn newtons_method(
 	}
 }
 
+/// Inputs `Vec<Option<T>>` and outputs a `String` containing a pretty
+/// representation of the Vector
+pub fn option_vec_printer<T: ToString>(data: Vec<Option<T>>) -> String {
+	let none_representation = "None";
+	let unwrapped: Vec<String> = data
+		.iter()
+		.map(|x| {
+			if let Some(inner) = x {
+				inner.to_string()
+			} else {
+				none_representation.to_owned()
+			}
+		})
+		.collect();
+
+	let mut output: String = String::from("[");
+	let mut curr_len: usize = 0;
+	let total_len: usize = unwrapped.len();
+	for ele in unwrapped.iter() {
+		curr_len += 1;
+		output += ele;
+		if total_len > curr_len {
+			output += ", ";
+		}
+	}
+	output += "]";
+	output
+}
+
 // Returns a vector of length `max_i` starting at value `min_x` with resolution
 // of `resolution`
 pub fn resolution_helper(max_i: usize, min_x: f64, resolution: f64) -> Vec<f64> {