add unit test for variance

src/base/mod.rs

@@ -64,3 +64,5 @@ pub use self::matrix_view::*;
 pub use self::storage::*;
 #[cfg(any(feature = "std", feature = "alloc"))]
 pub use self::vec_storage::*;
+
+mod variance_test;

src/base/variance_test.rs

@@ -0,0 +1,7 @@
+#[cfg(test)]
+use crate::DVector;
+#[test]
+fn test_variance_new() {
+    let v = DVector::repeat(10_000, 100000000.1234);
+    assert_eq!(v.variance(), 0.0)
+}