More types

src/Numerics/BasicMath.php

@@ -25,7 +25,7 @@ class BasicMath
      * Sums the items in $itemsToSum
      *
      * @param  array    $itemsToSum The items to sum,
-     * @param  callable $callback   The function to apply to each array element before summing.
+     * @param  \Closure $callback   The function to apply to each array element before summing.
      * @return number The sum.
      */
     public static function sum(array $itemsToSum, \Closure $callback): float|int

src/Numerics/Matrix.php

@@ -57,7 +57,7 @@ class Matrix
         return $this->matrixRowData[$row][$col];
     }
 
-    public function setValue(int $row, int $col, float|int $value)
+    public function setValue(int $row, int $col, float|int $value): void
     {
         $this->matrixRowData[$row][$col] = $value;
     }