Circle-Packings/fractal_dimension/bai_finch_rust/src/main.rs
William Ball 393d2d0529 prisms
2021-07-16 15:24:32 -04:00

271 lines
9.2 KiB
Rust

#![allow(dead_code)]
use num_complex::Complex64;
type F = f64;
type Matrix2x2 = nalgebra::SMatrix<Complex64, 2, 2>;
type MatrixBig = nalgebra::DMatrix<Complex64>;
type MatrixBigr = nalgebra::DMatrix<f64>;
const G: Matrix2x2 = Matrix2x2::new(
Complex64::new(2.0 / 12.0, -2.0 / 12.0),
Complex64::new(-1.0 / 12.0, -5.0 / 12.0),
Complex64::new(4.0 / 12.0, -4.0 / 12.0),
Complex64::new(-2.0 / 12.0, -10.0 / 12.0),
);
const R: Matrix2x2 = Matrix2x2::new(
Complex64::new(-6.0 / 12.0, 8.0 / 12.0),
Complex64::new(0.0, 11.0 / 12.0),
Complex64::new(0.0, 4.0 / 12.0),
Complex64::new(-6.0 / 12.0, -8.0 / 12.0),
);
const NC: usize = 5;
const K0: i32 = 100;
const LC: usize = 3;
const NC2: usize = NC * NC;
const UPPER_BOUND: i32 = 10_000;
fn fancy_l(q: f64) -> MatrixBigr {
let mut fancy_l = MatrixBigr::zeros(NC2, NC2);
for m in 0..NC {
for n in 0..NC {
for r in 0..NC {
for s in 0..NC {
if m <= n {
let mut sum_m = Complex64::new(0.0, 0.0);
for k in 1..K0 {
sum_m += normal_m(k, q, n as i32, s as i32)
* normal_m(k as i32, q, m as i32, r as i32).conj();
}
let sum_f = (0..=LC)
.map(|l: usize| -> Complex64 {
zeta(l as f64 + 2.0 * q, K0)
* (0..=l)
.map(|lp| {
normal_f(q, m as i32, r as i32, (l - lp) as i32)
* normal_f(q, n as i32, s as i32, lp as i32).conj()
})
.sum::<Complex64>()
})
.sum::<Complex64>();
fancy_l[(m * NC + n, r * NC + s)] = 2.0 * (sum_m.re + sum_f.re);
} else {
fancy_l[(m * NC + n, r * NC + s)] = fancy_l[(n * NC + m, s * NC + r)];
}
}
}
}
}
fancy_l
// MatrixBigr::from_diagonal_element(NC2, NC2, 2.0) * (fancy_m(q) + fancy_f(q)).map(|z| z.re)
}
fn integral_choose(n: i32, k: i32) -> f64 {
match k.cmp(&0) {
std::cmp::Ordering::Less => 0.0,
std::cmp::Ordering::Equal => 1.0,
std::cmp::Ordering::Greater => (0..k).map(|i| (n - i) as f64 / (k - i) as f64).product(),
}
}
fn non_integral_choose(q: f64, k: i32) -> f64 {
match k.cmp(&0) {
std::cmp::Ordering::Less => 0.0,
std::cmp::Ordering::Equal => 1.0,
std::cmp::Ordering::Greater => (0..k).map(|i| (q - i as f64) / (k - i) as f64).product(),
}
}
fn normal_f(q: f64, n: i32, s: i32, l: i32) -> Complex64 {
let r11 = R[(0, 0)];
let r12 = R[(0, 1)];
let r21 = R[(1, 0)];
let r22 = R[(1, 1)];
let g11 = G[(0, 0)];
let g12 = G[(0, 1)];
let g21 = G[(1, 0)];
let g22 = G[(1, 1)];
(0..=s)
.into_iter()
.map(|j: i32| -> Complex64 {
non_integral_choose(-n as f64 - q, j)
* integral_choose(n, s - j)
* (0..=j)
.map(|l1: i32| -> Complex64 {
(0..=(s - j))
.map(|l3: i32| -> Complex64 {
(0..=(n - s + j))
.map(|l4: i32| -> Complex64 {
integral_choose(j, l1)
* non_integral_choose(
-n as f64 - q - j as f64,
l - l1 - l3 - l4,
)
* integral_choose(s - j, l3)
* integral_choose(n - s + j, l4)
* r21.powi(l1)
* r22.powi(l - l1 - l3 - l4)
* r11.powi(l3)
* r12.powi(l4)
* g21.powi(j - l1)
* g22.powf(
-n as f64 - q - j as f64 - l as f64
+ l1 as f64
+ l3 as f64
+ l4 as f64,
)
* g11.powi(s - j - l3)
* g12.powi(n - s + j - l4)
})
.sum()
})
.sum()
})
.sum::<Complex64>()
})
.sum()
}
fn zeta(s: f64, k0: i32) -> f64 {
(k0..=UPPER_BOUND)
.into_iter()
.map(|j| (j as f64).powf(-s))
.sum::<f64>()
- (UPPER_BOUND as f64).powf(1.0 - s) / (1.0 - s)
}
fn fancy_f(q: f64) -> MatrixBig {
let mut fancy_f = MatrixBig::zeros(NC2, NC2);
for m in 0..NC {
for n in 0..NC {
for r in 0..NC {
for s in 0..NC {
if m <= n {
fancy_f[(m * NC + n, r * NC + s)] = (0..=LC)
.map(|l: usize| -> Complex64 {
zeta(l as f64 + 2.0 * q, K0)
* (0..=l)
.map(|lp| {
normal_f(q, m as i32, r as i32, (l - lp) as i32)
* normal_f(q, n as i32, s as i32, lp as i32).conj()
})
.sum::<Complex64>()
})
.sum::<Complex64>();
} else {
fancy_f[(m * NC + n, r * NC + s)] =
fancy_f[(n * NC + m, s * NC + r)].conj();
}
}
}
}
}
fancy_f
}
fn normal_m(k: i32, q: f64, n: i32, s: i32) -> Complex64 {
let ak = R + Matrix2x2::from_diagonal_element(Complex64::new(k as f64, 0.0)) * G;
let a11 = ak[(0, 0)];
let a12 = ak[(0, 1)];
let a21 = ak[(1, 0)];
let a22 = ak[(1, 1)];
(0..=s)
.into_iter()
.map(|j| {
non_integral_choose(-n as f64 - q, j)
* integral_choose(n, s - j)
* a21.powi(j)
* a22.powf(-n as f64 - q - j as f64)
* a11.powi(s - j)
* a12.powi(n - s + j)
})
.sum()
}
fn fancy_m(q: f64) -> MatrixBig {
let mut fancy_m = MatrixBig::zeros(NC2, NC2);
for m in 0..NC {
for n in 0..NC {
for r in 0..NC {
for s in 0..NC {
if m <= n {
let mut sum = Complex64::new(0.0, 0.0);
for k in 1..K0 {
sum += normal_m(k, q, n as i32, s as i32)
* normal_m(k as i32, q, m as i32, r as i32).conj();
}
fancy_m[(m * NC + n, r * NC + s)] = sum;
} else {
fancy_m[(m * NC + n, r * NC + s)] =
fancy_m[(n * NC + m, s * NC + r)].conj();
}
}
}
}
}
fancy_m
}
fn secant_method(f: fn(F) -> F, target: F, x0: F, x1: F, accuracy: F, iterations: usize) -> F {
let mut x0 = x0;
let mut x1 = x1;
let mut y0 = f(x0);
let mut y1 = f(x1);
let mut count = 0;
println!("f({}) =\t{}", x1, y1);
while (y1 - target).abs() >= accuracy && count < iterations {
let new_x = x0 - (y0 - target) * (x1 - x0) / (y1 - y0);
x0 = x1;
x1 = new_x;
y0 = y1;
y1 = f(x1);
println!("f({}) =\t{}", x1, y1);
count += 1;
}
x0
}
fn power_method(
vec: nalgebra::DVector<f64>,
mat: nalgebra::DMatrix<f64>,
iterations: usize,
tolerance: f64,
) -> f64 {
let mut previous_entry = vec[0];
let mut previous_val = 0f64;
let mut current = mat.clone() * vec;
let mut current_val = current[0] / previous_entry;
let mut count = 0;
while count < iterations && (current_val - previous_val).abs() > tolerance {
previous_val = current_val;
previous_entry = current[0];
current = mat.clone() * current;
current_val = current[0] / previous_entry;
count += 1;
}
println!("found eigenvalue {} in {} iterations", current_val, count);
current_val
}
fn test(x: f64) -> f64 {
x.cos() - x
}
fn lambda(q: f64) -> f64 {
let lq = fancy_l(q);
let mut phi0 = nalgebra::DVector::zeros(NC2);
phi0[0] = 1.0;
power_method(phi0, lq, 50, std::f64::EPSILON)
}
fn main() {
// secant_method(lambda, 1.0, 1.3, 1.31, f64::EPSILON, 100);
// secant_method(test, 0.0, 0.0, 1.0, f64::EPSILON, 100);
println!("{}", normal_m(5, 1.3, 3, 3));
}