relu

Author: motsat

ch01/forward_and_backward.py

@@ -23,6 +23,24 @@ def backword(self, dout):
         # xに対して1.1という値の打ち消し微分を渡したいので。
         return dx, dy
 
+class AddLayer:
+    def __init__(self):
+        self.x = None
+        self.y = None
+        return
+
+    def forward(self, x, y):
+        self.x = x
+        self.y = y
+        return x + y
+
+    # doutは逆伝播時の微分値
+    # このメソッドは出力として微分値を返します
+    def backword(self, dout):
+        dx = dout * 1
+        dy = dout * 1
+        return dx, dy
+
 origin_price = 100
 buy_count = 2
 tax = 1.1

ch01/relu.py

@@ -0,0 +1,20 @@
+import numpy as np
+class ReluLayer:
+    def __init__(self):
+        self.mask = None
+
+    def forward(self, x):
+        self.mask = (x <= 0)
+        out = x.copy()
+        # マスク部分を0にする
+        # [[ 2.  -0.6]
+        #  [ 1.  -0.5]]
+        #   => 
+        #    [[ 2.  0.]
+        #     [ 1.  0.]]
+        out[self.mask] = 0
+        return out
+
+x = np.array([[2.0,-0.6], [1.0,-0.5]])
+relu_layer = ReluLayer()
+relu_layer.forward(x)