From 7e38f45a3f1ef13d5b2f4ea89bcd3cda69ee5e9f Mon Sep 17 00:00:00 2001
From: Connor Olding <cloningdonor@gmail.com>
Date: Fri, 9 Jun 2017 12:32:44 +0000
Subject: [PATCH] add cosine activation

---
 optim_nn_core.py | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/optim_nn_core.py b/optim_nn_core.py
index feba346..179389a 100644
--- a/optim_nn_core.py
+++ b/optim_nn_core.py
@@ -672,6 +672,16 @@ class LogSoftmax(Softmax):
     def backward(self, dY):
         return dY - np.sum(dY, axis=-1, keepdims=True) * self.sm
 
+class Cos(Layer):
+    # performs well on MNIST for some strange reason.
+
+    def forward(self, X):
+        self.X = X
+        return np.cos(X)
+
+    def backward(self, dY):
+        return dY * -np.sin(self.X)
+
 # Parametric Layers {{{1
 
 class Dense(Layer):