Merge pull request #6 from KastusKalinovski/master

Master

.gitignore

@@ -0,0 +1,63 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+env/
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+*.egg-info/
+.installed.cfg
+*.egg
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.coverage
+.cache
+nosetests.xml
+coverage.xml
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+target/
+
+# IPython notebook
+.ipynb_checkpoints
+
+# Repo scratch directory
+scratch/
+
+# Misc
+.DS_Store

src/layers/activations.py

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+import numpy as np
+from src.utils import sigmoid
+
+class Relu:
+    '''Rectified Linear Unit activation function'''
+    def __init__(self):
+        self.params = []
+
+    def forward(self, batch):
+        self.X = batch
+        return np.maximum(0, self.X)
+
+    def backward(self, gradient):
+        flow_gradient = gradient.copy()
+        flow_gradient[self.X <= 0] = 0
+        return flow_gradient, []
+
+
+class Sigmoid():
+    '''Sigmoid activation function'''
+    def __init__(self):
+        self.params = []
+
+    def forward(self, batch):
+        self.X = np.array(sigmoid(x) for x in batch)
+        return self.X
+
+    def backward(self, gradient):
+        flow_gradient = gradient*self.X*(1-self.X)
+        return flow_gradient, []