chore: import upstream snapshot with attribution

books/PRML/PRML-master-Python/test/nn/array/flatten.py

@@ -0,0 +1,21 @@
+import unittest
+import numpy as np
+from prml import nn
+
+
+class TestFlatten(unittest.TestCase):
+
+    def test_flatten(self):
+        self.assertRaises(TypeError, nn.flatten, "abc")
+        self.assertRaises(ValueError, nn.flatten, np.ones(1))
+
+        x = np.random.rand(5, 4)
+        p = nn.Parameter(x)
+        y = p.flatten()
+        self.assertTrue((y.value == x.flatten()).all())
+        y.backward(np.ones(20))
+        self.assertTrue((p.grad == np.ones((5, 4))).all())
+
+
+if __name__ == '__main__':
+    unittest.main()