Initial commit

data/mnist_loader.py

@@ -0,0 +1,31 @@
+import struct
+
+import numpy as np
+
+from neural_net.neural_net import ModelData
+
+class MNISTModelData(ModelData):
+    def __init__(self, fn_train_inputs, fn_train_targets, fn_test_inputs, fn_test_targets):
+        super().__init__(
+            self._get_images_from_idx(fn_train_inputs),
+            self._get_labels_from_idx(fn_train_targets),
+            self._get_images_from_idx(fn_test_inputs),
+            self._get_labels_from_idx(fn_test_targets)
+        )
+        print(np.array(self.test_inputs[0]).reshape((28, 28)))
+
+    def _get_images_from_idx(self, file):
+        with open(file, 'rb') as f:
+            magic, size = struct.unpack(">II", f.read(8))
+            nrows, ncols = struct.unpack(">II", f.read(8))
+
+            data = np.fromfile(f, dtype=np.dtype(np.uint8).newbyteorder('>'))
+            data = data.reshape((size, nrows * ncols)) / 255
+
+            return 1 - data
+
+    def _get_labels_from_idx(self, file):
+        with open(file, 'rb') as f:
+            magic, size = struct.unpack(">II", f.read(8))
+            data = np.fromfile(f, dtype=np.dtype(np.uint8).newbyteorder('>'))
+            return data