Refine the log calculation in Transformer beam search

fluid/neural_machine_translation/transformer/infer.py

@@ -121,11 +121,11 @@ def translate_batch(exe, src_words, encoder, enc_in_names, enc_out_names,
         predict_all = exe.run(decoder,
                               feed=dict(zip(dec_in_names, dec_in_data)),
                               fetch_list=dec_out_names)[0]
-        predict_all = np.log(predict_all)
-        predict_all = (
-            predict_all.reshape(
-                [len(beam_map) * beam_size, i + 1, -1])[:, -1, :] +
-            scores[beam_map].reshape([len(beam_map) * beam_size, -1])).reshape(
+        predict_all = np.log(
+            predict_all.reshape([len(beam_map) * beam_size, i + 1, -1])[:,
+                                                                        -1, :])
+        predict_all = (predict_all + scores[beam_map].reshape(
+            [len(beam_map) * beam_size, -1])).reshape(
                 [len(beam_map), beam_size, -1])
         active_beams = []
         for inst_idx, beam_idx in enumerate(beam_map):