Intial commit

Author: andrewdalpino

…ELU/Exceptions/InvalidAlphaException.php src/Exceptions/InvalidAlphaException.phpsrc/NeuralNet/ActivationFunctions/ELU/Exceptions/InvalidAlphaException.php renamed to src/Exceptions/InvalidAlphaException.php src/NeuralNet/ActivationFunctions/ELU/Exceptions/InvalidAlphaException.php renamed to src/Exceptions/InvalidAlphaException.php

@@ -1,8 +1,10 @@
 <?php
 
-namespace Rubix\ML\NeuralNet\ActivationFunctions;
+declare(strict_types=1);
 
-use Tensor\Matrix;
+namespace Rubix\ML\NeuralNet\ActivationFunctions\Base\Contracts;
+
+use NDArray;
 use Stringable;
 
 /**
@@ -11,27 +13,15 @@
  * @category    Machine Learning
  * @package     Rubix/ML
  * @author      Andrew DalPino
+ * @author      Aleksei Nechaev <omfg.rus@gmail.com>
  */
 interface ActivationFunction extends Stringable
 {
     /**
      * Compute the activation.
      *
-     * @internal
-     *
-     * @param Matrix $input
-     * @return Matrix
-     */
-    public function activate(Matrix $input) : Matrix;
-
-    /**
-     * Calculate the derivative of the activation.
-     *
-     * @internal
-     *
-     * @param Matrix $input
-     * @param Matrix $output
-     * @return Matrix
+     * @param NDArray $input Input matrix
+     * @return NDArray Output matrix
      */
-    public function differentiate(Matrix $input, Matrix $output) : Matrix;
+    public function activate(NDArray $input) : NDArray;
 }