Enhance Matrix implementation with generic filled method and add NaN support

src/matrix/mat.rs

@@ -361,17 +361,18 @@ impl<T: Clone> Matrix<T> {
         }
         Matrix::from_vec(data, n, self.cols)
     }
-}
 
-impl Matrix<f64> {
     /// Creates a new matrix filled with a specific value of the specified size.
-    pub fn filled(rows: usize, cols: usize, value: f64) -> Self {
+    pub fn filled(rows: usize, cols: usize, value: T) -> Self {
         Matrix {
             rows,
             cols,
             data: vec![value; rows * cols], // Fill with the specified value
         }
     }
+}
+
+impl Matrix<f64> {
     /// Creates a new matrix filled with zeros of the specified size.
     pub fn zeros(rows: usize, cols: usize) -> Self {
         Matrix::filled(rows, cols, 0.0)
@@ -381,6 +382,11 @@ impl Matrix<f64> {
     pub fn ones(rows: usize, cols: usize) -> Self {
         Matrix::filled(rows, cols, 1.0)
     }
+
+    /// Creates a new matrix filled with NaN values of the specified size.
+    pub fn nan(rows: usize, cols: usize) -> Matrix<f64> {
+        Matrix::filled(rows, cols, f64::NAN)
+    }
 }
 
 impl<T> Index<(usize, usize)> for Matrix<T> {
@@ -1929,5 +1935,19 @@ mod tests {
         assert_eq!(m.rows(), 2);
         assert_eq!(m.cols(), 2);
         assert_eq!(m.data(), &[42.5, 42.5, 42.5, 42.5]);
+
+        // test with an integer matrix
+        let m = Matrix::<i32>::filled(2, 3, 7);
+        assert_eq!(m.rows(), 2);
+        assert_eq!(m.cols(), 3);
+        assert_eq!(m.data(), &[7, 7, 7, 7, 7, 7]);
+
+        // test with nans
+        let m = Matrix::nan(3, 3);
+        assert_eq!(m.rows(), 3);
+        assert_eq!(m.cols(), 3);
+        for &value in m.data() {
+            assert!(value.is_nan(), "Expected NaN, got {}", value);
+        }
     }
 }