YTBN-Graphing-Software/src/function_entry.rs
2023-11-20 12:40:41 -05:00

479 lines
12 KiB
Rust

use crate::math_app::AppSettings;
use crate::misc::{newtons_method_helper, step_helper, EguiHelper};
use egui::{Checkbox, Context};
use egui_plot::{Bar, BarChart, PlotPoint, PlotUi};
use epaint::Color32;
use parsing::{generate_hint, AutoComplete};
use parsing::{process_func_str, BackingFunction};
use serde::{ser::SerializeStruct, Deserialize, Deserializer, Serialize, Serializer};
use std::{
fmt::{self, Debug},
hash::{Hash, Hasher},
intrinsics::assume,
};
/// Represents the possible variations of Riemann Sums
#[derive(PartialEq, Eq, Debug, Copy, Clone, Default)]
pub enum Riemann {
#[default]
Left,
Middle,
Right,
}
impl fmt::Display for Riemann {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "{:?}", self) }
}
/// `FunctionEntry` is a function that can calculate values, integrals, derivatives, etc etc
#[derive(Clone)]
pub struct FunctionEntry {
/// The `BackingFunction` instance that is used to generate `f(x)`, `f'(x)`, and `f''(x)`
function: BackingFunction,
/// Stores a function string (that hasn't been processed via `process_func_str`) to display to the user
pub raw_func_str: String,
/// If calculating/displayingintegrals are enabled
pub integral: bool,
/// If displaying derivatives are enabled (note, they are still calculated for other purposes)
pub derivative: bool,
pub nth_derviative: bool,
pub back_data: Vec<PlotPoint>,
pub integral_data: Option<(Vec<Bar>, f64)>,
pub derivative_data: Vec<PlotPoint>,
pub extrema_data: Vec<PlotPoint>,
pub root_data: Vec<PlotPoint>,
nth_derivative_data: Option<Vec<PlotPoint>>,
pub autocomplete: AutoComplete<'static>,
test_result: Option<String>,
curr_nth: usize,
pub settings_opened: bool,
}
impl Hash for FunctionEntry {
fn hash<H: Hasher>(&self, state: &mut H) {
self.raw_func_str.hash(state);
self.integral.hash(state);
self.nth_derviative.hash(state);
self.curr_nth.hash(state);
self.settings_opened.hash(state);
}
}
impl Serialize for FunctionEntry {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut s = serializer.serialize_struct("FunctionEntry", 4)?;
s.serialize_field("raw_func_str", &self.raw_func_str)?;
s.serialize_field("integral", &self.integral)?;
s.serialize_field("derivative", &self.derivative)?;
s.serialize_field("curr_nth", &self.curr_nth)?;
s.end()
}
}
impl<'de> Deserialize<'de> for FunctionEntry {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
#[derive(Deserialize)]
struct Helper {
raw_func_str: String,
integral: bool,
derivative: bool,
curr_nth: usize,
}
let helper = Helper::deserialize(deserializer)?;
let mut new_func_entry = FunctionEntry::EMPTY;
let gen_func = BackingFunction::new(&helper.raw_func_str);
match gen_func {
Ok(func) => new_func_entry.function = func,
Err(x) => new_func_entry.test_result = Some(x),
}
new_func_entry.autocomplete = AutoComplete {
i: 0,
hint: generate_hint(&helper.raw_func_str),
string: helper.raw_func_str,
};
new_func_entry.integral = helper.integral;
new_func_entry.derivative = helper.derivative;
new_func_entry.curr_nth = helper.curr_nth;
Ok(new_func_entry)
}
}
impl const Default for FunctionEntry {
/// Creates default FunctionEntry instance (which is empty)
fn default() -> FunctionEntry { FunctionEntry::EMPTY }
}
impl FunctionEntry {
pub const EMPTY: FunctionEntry = FunctionEntry {
function: BackingFunction::EMPTY,
raw_func_str: String::new(),
integral: false,
derivative: false,
nth_derviative: false,
back_data: Vec::new(),
integral_data: None,
derivative_data: Vec::new(),
extrema_data: Vec::new(),
root_data: Vec::new(),
nth_derivative_data: None,
autocomplete: AutoComplete::EMPTY,
test_result: None,
curr_nth: 3,
settings_opened: false,
};
pub const fn is_some(&self) -> bool { !self.function.is_none() }
pub fn settings_window(&mut self, ctx: &Context) {
let mut invalidate_nth = false;
egui::Window::new(format!("Settings: {}", self.raw_func_str))
.open(&mut self.settings_opened)
.default_pos([200.0, 200.0])
.resizable(false)
.collapsible(false)
.show(ctx, |ui| {
ui.add(Checkbox::new(
&mut self.nth_derviative,
"Display Nth Derivative",
));
if ui
.add(egui::Slider::new(&mut self.curr_nth, 3..=5).text("Nth Derivative"))
.changed()
{
invalidate_nth = true;
}
});
if invalidate_nth {
self.clear_nth();
}
}
/// Get function's cached test result
pub fn get_test_result(&self) -> &Option<String> { &self.test_result }
/// Update function string and test it
pub fn update_string(&mut self, raw_func_str: &str) {
if raw_func_str == self.raw_func_str {
return;
}
self.raw_func_str = raw_func_str.to_owned();
let processed_func = process_func_str(raw_func_str);
let new_func_result = BackingFunction::new(&processed_func);
match new_func_result {
Ok(new_function) => {
self.test_result = None;
self.function = new_function;
self.invalidate_whole();
}
Err(error) => {
self.test_result = Some(error);
}
}
}
/// Creates and does the math for creating all the rectangles under the graph
fn integral_rectangles(
&self, integral_min_x: f64, integral_max_x: f64, sum: Riemann, integral_num: usize,
) -> (Vec<(f64, f64)>, f64) {
let step = (integral_max_x - integral_min_x) / (integral_num as f64);
// let sum_func = self.get_sum_func(sum);
let data2: Vec<(f64, f64)> = step_helper(integral_num, integral_min_x, step)
.into_iter()
.map(|x| {
let step_offset = step.copysign(x); // store the offset here so it doesn't have to be calculated multiple times
let x2: f64 = x + step_offset;
let (left_x, right_x) = match x.is_sign_positive() {
true => (x, x2),
false => (x2, x),
};
let y = match sum {
Riemann::Left => self.function.get(left_x),
Riemann::Right => self.function.get(right_x),
Riemann::Middle => {
(self.function.get(left_x) + self.function.get(right_x)) / 2.0
}
};
(x + (step_offset / 2.0), y)
})
.filter(|(_, y)| y.is_finite())
.collect();
let area = data2.iter().map(move |(_, y)| y * step).sum();
(data2, area)
}
/// Helps with processing newton's method depending on level of derivative
fn newtons_method_helper(
&self, threshold: f64, derivative_level: usize, range: &std::ops::Range<f64>,
) -> Vec<PlotPoint> {
let newtons_method_output: Vec<f64> = match derivative_level {
0 => newtons_method_helper(
threshold,
range,
self.back_data.as_slice(),
&|x: f64| self.function.get(x),
&|x: f64| self.function.get_derivative_1(x),
),
1 => newtons_method_helper(
threshold,
range,
self.derivative_data.as_slice(),
&|x: f64| self.function.get_derivative_1(x),
&|x: f64| self.function.get_derivative_2(x),
),
_ => unreachable!(),
};
newtons_method_output
.into_iter()
.map(|x| PlotPoint::new(x, self.function.get(x)))
.collect()
}
/// Does the calculations and stores results in `self`
pub fn calculate(
&mut self, width_changed: bool, min_max_changed: bool, did_zoom: bool,
settings: AppSettings,
) {
if self.test_result.is_some() | self.function.is_none() {
return;
}
let resolution = (settings.max_x - settings.min_x) / (settings.plot_width as f64);
debug_assert!(resolution > 0.0);
let resolution_iter = step_helper(settings.plot_width + 1, settings.min_x, resolution);
unsafe { assume(!resolution_iter.is_empty()) }
// Makes sure proper arguments are passed when integral is enabled
if self.integral && settings.integral_changed {
self.clear_integral();
}
if width_changed | min_max_changed | did_zoom {
self.clear_back();
self.clear_derivative();
self.clear_nth();
}
if self.back_data.is_empty() {
let data: Vec<PlotPoint> = resolution_iter
.clone()
.into_iter()
.map(|x| PlotPoint::new(x, self.function.get(x)))
.collect();
debug_assert_eq!(data.len(), settings.plot_width + 1);
self.back_data = data;
}
if self.derivative_data.is_empty() {
let data: Vec<PlotPoint> = resolution_iter
.clone()
.into_iter()
.map(|x| PlotPoint::new(x, self.function.get_derivative_1(x)))
.collect();
debug_assert_eq!(data.len(), settings.plot_width + 1);
self.derivative_data = data;
}
if self.nth_derviative && self.nth_derivative_data.is_none() {
let data: Vec<PlotPoint> = resolution_iter
.into_iter()
.map(|x| PlotPoint::new(x, self.function.get_nth_derivative(self.curr_nth, x)))
.collect();
debug_assert_eq!(data.len(), settings.plot_width + 1);
self.nth_derivative_data = Some(data);
}
if self.integral {
if self.integral_data.is_none() {
let (data, area) = self.integral_rectangles(
settings.integral_min_x,
settings.integral_max_x,
settings.riemann_sum,
settings.integral_num,
);
self.integral_data = Some((
data.into_iter().map(|(x, y)| Bar::new(x, y)).collect(),
area,
));
}
} else {
self.clear_integral();
}
let threshold: f64 = resolution / 2.0;
let x_range = settings.min_x..settings.max_x;
// Calculates extrema
if settings.do_extrema && (min_max_changed | self.extrema_data.is_empty()) {
self.extrema_data = self.newtons_method_helper(threshold, 1, &x_range);
}
// Calculates roots
if settings.do_roots && (min_max_changed | self.root_data.is_empty()) {
self.root_data = self.newtons_method_helper(threshold, 0, &x_range);
}
}
/// Displays the function's output on PlotUI `plot_ui` with settings `settings`.
/// Returns an `Option<f64>` of the calculated integral.
pub fn display(
&self, plot_ui: &mut PlotUi, settings: &AppSettings, main_plot_color: Color32,
) -> Option<f64> {
if self.test_result.is_some() | self.function.is_none() {
return None;
}
let integral_step =
(settings.integral_max_x - settings.integral_min_x) / (settings.integral_num as f64);
debug_assert!(integral_step > 0.0);
let step = (settings.max_x - settings.min_x) / (settings.plot_width as f64);
debug_assert!(step > 0.0);
// Plot back data
if !self.back_data.is_empty() {
if self.integral && (step >= integral_step) {
plot_ui.line(
self.back_data
.iter()
.filter(|value| {
(value.x > settings.integral_min_x)
&& (settings.integral_max_x > value.x)
})
.cloned()
.collect::<Vec<PlotPoint>>()
.to_line()
.stroke(epaint::Stroke::NONE)
.color(Color32::from_rgb(4, 4, 255))
.fill(0.0),
);
}
plot_ui.line(
self.back_data
.clone()
.to_line()
.stroke(egui::Stroke::new(4.0, main_plot_color)),
);
}
// Plot derivative data
if self.derivative && !self.derivative_data.is_empty() {
plot_ui.line(self.derivative_data.clone().to_line().color(Color32::GREEN));
}
// Plot extrema points
if settings.do_extrema && !self.extrema_data.is_empty() {
plot_ui.points(
self.extrema_data
.clone()
.to_points()
.color(Color32::YELLOW)
.radius(5.0), // Radius of points of Extrema
);
}
// Plot roots points
if settings.do_roots && !self.root_data.is_empty() {
plot_ui.points(
self.root_data
.clone()
.to_points()
.color(Color32::LIGHT_BLUE)
.radius(5.0), // Radius of points of Roots
);
}
if self.nth_derviative
&& let Some(ref nth_derviative) = self.nth_derivative_data
{
plot_ui.line(nth_derviative.clone().to_line().color(Color32::DARK_RED));
}
// Plot integral data
match &self.integral_data {
Some(integral_data) => {
if integral_step > step {
plot_ui.bar_chart(
BarChart::new(integral_data.0.clone())
.color(Color32::BLUE)
.width(integral_step),
);
}
// return value rounded to 8 decimal places
Some(emath::round_to_decimals(integral_data.1, 8))
}
None => None,
}
}
/// Invalidate entire cache
fn invalidate_whole(&mut self) {
self.clear_back();
self.clear_integral();
self.clear_derivative();
self.clear_nth();
self.clear_extrema();
self.clear_roots();
}
/// Invalidate `back` data
#[inline]
fn clear_back(&mut self) { self.back_data.clear(); }
/// Invalidate Integral data
#[inline]
fn clear_integral(&mut self) { self.integral_data = None; }
/// Invalidate Derivative data
#[inline]
fn clear_derivative(&mut self) { self.derivative_data.clear(); }
/// Invalidates `n`th derivative data
#[inline]
fn clear_nth(&mut self) { self.nth_derivative_data = None }
/// Invalidate extrema data
#[inline]
fn clear_extrema(&mut self) { self.extrema_data.clear() }
/// Invalidate root data
#[inline]
fn clear_roots(&mut self) { self.root_data.clear() }
}