From c004bd8334cbac89bc244f2c4b2d661d37f38d4e Mon Sep 17 00:00:00 2001
From: Palash Tyagi <23239946+Magnus167@users.noreply.github.com>
Date: Sat, 26 Jul 2025 23:05:41 +0100
Subject: [PATCH] Add inferential statistics examples

---
 examples/inferential_stats.rs | 66 +++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 examples/inferential_stats.rs

diff --git a/examples/inferential_stats.rs b/examples/inferential_stats.rs
new file mode 100644
index 0000000..ac6b9b8
--- /dev/null
+++ b/examples/inferential_stats.rs
@@ -0,0 +1,66 @@
+use rustframe::compute::stats::{anova, chi2_test, t_test};
+use rustframe::matrix::Matrix;
+
+/// Demonstrates simple inferential statistics tests.
+fn main() {
+    t_test_demo();
+    println!("\n-----\n");
+    chi2_demo();
+    println!("\n-----\n");
+    anova_demo();
+}
+
+fn t_test_demo() {
+    println!("Two-sample t-test\n-----------------");
+    let a = Matrix::from_vec(vec![1.0, 2.0, 3.0, 4.0, 5.0], 1, 5);
+    let b = Matrix::from_vec(vec![6.0, 7.0, 8.0, 9.0, 10.0], 1, 5);
+    let (t, p) = t_test(&a, &b);
+    println!("t statistic: {:.2}, p-value: {:.4}", t, p);
+}
+
+fn chi2_demo() {
+    println!("Chi-square test\n---------------");
+    let observed = Matrix::from_vec(vec![12.0, 5.0, 8.0, 10.0], 2, 2);
+    let (chi2, p) = chi2_test(&observed);
+    println!("chi^2: {:.2}, p-value: {:.4}", chi2, p);
+}
+
+fn anova_demo() {
+    println!("One-way ANOVA\n-------------");
+    let g1 = Matrix::from_vec(vec![1.0, 2.0, 3.0], 1, 3);
+    let g2 = Matrix::from_vec(vec![2.0, 3.0, 4.0], 1, 3);
+    let g3 = Matrix::from_vec(vec![3.0, 4.0, 5.0], 1, 3);
+    let (f, p) = anova(vec![&g1, &g2, &g3]);
+    println!("F statistic: {:.2}, p-value: {:.4}", f, p);
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_t_test_demo() {
+        let a = Matrix::from_vec(vec![1.0, 2.0, 3.0, 4.0, 5.0], 1, 5);
+        let b = Matrix::from_vec(vec![6.0, 7.0, 8.0, 9.0, 10.0], 1, 5);
+        let (t, _p) = t_test(&a, &b);
+        assert!((t + 5.0).abs() < 1e-5);
+    }
+
+    #[test]
+    fn test_chi2_demo() {
+        let observed = Matrix::from_vec(vec![12.0, 5.0, 8.0, 10.0], 2, 2);
+        let (chi2, p) = chi2_test(&observed);
+        assert!(chi2 > 0.0);
+        assert!(p > 0.0 && p < 1.0);
+    }
+
+    #[test]
+    fn test_anova_demo() {
+        let g1 = Matrix::from_vec(vec![1.0, 2.0, 3.0], 1, 3);
+        let g2 = Matrix::from_vec(vec![2.0, 3.0, 4.0], 1, 3);
+        let g3 = Matrix::from_vec(vec![3.0, 4.0, 5.0], 1, 3);
+        let (f, p) = anova(vec![&g1, &g2, &g3]);
+        assert!(f > 0.0);
+        assert!(p > 0.0 && p < 1.0);
+    }
+}