Implement Default for MatrixMN.

src/base/array_storage.rs

@@ -48,6 +48,19 @@ where
 /// Renamed to [ArrayStorage].
 pub type MatrixArray<N, R, C> = ArrayStorage<N, R, C>;
 
+impl<N, R, C> Default for ArrayStorage<N, R, C>
+where
+    R: DimName,
+    C: DimName,
+    R::Value: Mul<C::Value>,
+    Prod<R::Value, C::Value>: ArrayLength<N>,
+    N: Default,
+{
+    fn default() -> Self {
+        ArrayStorage { data: Default::default() }
+    }
+}
+
 impl<N, R, C> Hash for ArrayStorage<N, R, C>
 where
     N: Hash,

src/base/matrix.rs

@@ -90,6 +90,21 @@ impl<N: Scalar, R: Dim, C: Dim, S: fmt::Debug> fmt::Debug for Matrix<N, R, C, S>
     }
 }
 
+impl<N, R, C, S> Default for Matrix<N, R, C, S>
+where
+    N: Scalar,
+    R: Dim,
+    C: Dim,
+    S: Default,
+{
+    fn default() -> Self {
+        Matrix {
+            data: Default::default(),
+            _phantoms: PhantomData,
+        }
+    }
+}
+
 #[cfg(feature = "serde-serialize")]
 impl<N, R, C, S> Serialize for Matrix<N, R, C, S>
 where