From dc571838bbc8d8bf3a1f846fa8c22c3ff93cc4eb Mon Sep 17 00:00:00 2001
From: Daniel <sersmicro@gmail.com>
Date: Fri, 7 Aug 2015 15:03:38 +0200
Subject: [PATCH] Added check for symmetricity of input matrix

---
 src/linalg/decompositions.rs |  6 +++++-
 tests/mat.rs                 | 13 +++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/linalg/decompositions.rs b/src/linalg/decompositions.rs
index 01fad087..e56e8cc4 100644
--- a/src/linalg/decompositions.rs
+++ b/src/linalg/decompositions.rs
@@ -127,7 +127,11 @@ pub fn cholesky<N, V, VS, M>(m: &M) -> Result<M, &'static str>
               Sub<M, Output = M> + ColSlice<VS> +
               ApproxEq<N> + Copy {
 
-    let mut out = m.clone();
+    let mut out = m.clone().transpose();
+
+    if !ApproxEq::approx_eq(&out, &m) {
+        return Err("Cholesky: Input matrix is not symmetric");
+    }
 
     for i in 0..out.nrows() {
         for j in 0..(i+1) {
diff --git a/tests/mat.rs b/tests/mat.rs
index 62edbfd2..28878b40 100644
--- a/tests/mat.rs
+++ b/tests/mat.rs
@@ -658,6 +658,19 @@ fn test_cholesky_not_spd() {
     }
 }
 
+#[test]
+fn test_cholesky_not_symmetric() {
+    
+    let a : Mat2<f64> = Mat2::<f64>::new(1.0, 1.0, -1.0, 1.0);
+
+    let result = na::cholesky(&a);
+
+    match result {
+        Ok(_) => assert!(false),
+        Err(_) => assert!(true),
+    }
+}
+
 #[test]
 fn test_cholesky_mat1() {
     test_cholesky_impl!(Mat1<f64>);