add test_lookup_sparse_table_op

Author: jacquesqiao

python/paddle/fluid/tests/unittests/test_lookup_sparse_table_op.py

@@ -80,6 +80,33 @@ def check_with_place(self, place):
         assert (result_array2[3] == w_array[6]).all()
         assert (result_array2[4] == w_array[7]).all()
 
+        # create and run lookup_table operator
+        test_lookup_table = Operator(
+            "lookup_sparse_table",
+            W='W',
+            Ids='Ids',
+            Out='Out',
+            min=-5.0,
+            max=10.0,
+            seed=10,
+            is_test=True)
+
+        ids = scope.var("Ids").get_tensor()
+        unknown_id = [44, 22, 33]
+        ids_array2 = np.array([4, 2, 3, 7, 100000] + unknown_id).astype("int64")
+        ids.set(ids_array2, place)
+        test_lookup_table.run(scope, place)
+
+        result_array2 = np.array(out_tensor)
+        assert (result_array2[0] == w_array[5]).all()
+        assert (result_array2[1] == w_array[1]).all()
+        assert (result_array2[2] == w_array[2]).all()
+        assert (result_array2[3] == w_array[6]).all()
+        assert (result_array2[4] == w_array[7]).all()
+
+        for i in [5, 6, 7]:
+            assert np.all(result_array2[i] == 0)
+
     def test_w_is_selected_rows(self):
         places = [core.CPUPlace()]
         # currently only support CPU