[feat] implement 'batchnorm_forward' function #1

jeongjae96 · Feb 28, 2023 · c1977d5 · c1977d5
1 parent 156886f
commit c1977d5
Showing 1 changed file with 9 additions and 2 deletions.
diff --git a/cs231n_2022/assignment2/cs231n/layers.py b/cs231n_2022/assignment2/cs231n/layers.py
@@ -227,7 +227,13 @@ def batchnorm_forward(x, gamma, beta, bn_param):
         #######################################################################
         # *****START OF YOUR CODE (DO NOT DELETE/MODIFY THIS LINE)*****
 
-        pass
+        sample_mean = np.mean(x, axis=0)
+        sample_var = np.var(x, axis = 0)
+        normalized_x = (x - sample_mean) / (np.sqrt(sample_var + eps))
+        out = gamma * normalized_x + beta
+        cache = (x, sample_mean, sample_var, eps, normalized_x, gamma)
+        running_mean = momentum * running_mean + (1 - momentum) * sample_mean
+        running_var = momentum * running_var + (1 - momentum) * sample_var
 
         # *****END OF YOUR CODE (DO NOT DELETE/MODIFY THIS LINE)*****
         #######################################################################
@@ -242,7 +248,8 @@ def batchnorm_forward(x, gamma, beta, bn_param):
         #######################################################################
         # *****START OF YOUR CODE (DO NOT DELETE/MODIFY THIS LINE)*****
 
-        pass
+        normalized_x = (x - running_mean) / np.sqrt(eps + running_var)
+        out = gamma * normalized_x + beta
 
         # *****END OF YOUR CODE (DO NOT DELETE/MODIFY THIS LINE)*****
         #######################################################################