Rust version of IFS (algorithm-archivists#755)

* add the rust version of the ifs

* Apply suggestions from code review

Co-authored-by: Dimitri Belopopsky <[email protected]>
Co-authored-by: stormofice <[email protected]>

* add a cargo toml

Co-authored-by: Dimitri Belopopsky <[email protected]>
Co-authored-by: stormofice <[email protected]>

contents/IFS/IFS.md

@@ -144,6 +144,8 @@ Here, instead of tracking children of children, we track a single individual tha
 [import:5-14, lang:"lisp"](code/clisp/ifs.lisp)
 {% sample lang="coco" %}
 [import:4-16, lang:"coconut"](code/coconut/IFS.coco)
+{% sample lang="rust" %}
+[import:9-20, lang:"rust"](code/rust/IFS.rs)
 {% sample lang="java" %}
 [import:16-39, lang:"java"](code/java/IFS.java)
 {% sample lang="ps1" %}
@@ -232,6 +234,8 @@ In addition, we have written the chaos game code to take in a set of points so t
 [import, lang:"lisp"](code/clisp/ifs.lisp)
 {%sample lang="coco" %}
 [import, lang:"coconut"](code/coconut/IFS.coco)
+{%sample lang="rust" %}
+[import, lang:"rust"](code/rust/IFS.rs)
 {%sample lang="java" %}
 [import, lang:"java"](code/java/IFS.java)
 {% sample lang="ps1" %}

contents/IFS/code/rust/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "rust"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+rand = "0.8.4"
+
+[[bin]]
+path = "./IFS.rs"
+name = "main"

contents/IFS/code/rust/IFS.rs

@@ -0,0 +1,36 @@
+use rand::*;
+
+#[derive(Clone, Copy)]
+struct Point {
+    x: f64,
+    y: f64,
+}
+
+fn chaos_game(iters: usize, shapes: Vec<Point>) -> Vec<Point> {
+    let mut rng = rand::thread_rng();
+    let mut p   = Point{x: rng.gen(), y: rng.gen()};
+
+    (0..iters).into_iter().map(|_| {
+        let old_point = p;
+        let tmp = shapes[rng.gen_range(0..shapes.len())];
+        p.x = 0.5 * (p.x + tmp.x);
+        p.y = 0.5 * (p.y + tmp.y);
+        old_point
+    }).collect()
+}
+
+fn main() {
+    let shapes = vec![
+        Point{x: 0., y: 0.},
+        Point{x: 0.5, y: 0.75_f64.sqrt()},
+        Point{x: 1., y: 0.},
+    ];
+
+    let mut out = String::new();
+
+    for point in chaos_game(10_000, shapes) {
+        out += format!("{}\t{}\n", point.x, point.y).as_str();
+    }
+
+    std::fs::write("./sierpinski.dat", out).unwrap();
+}