{"action":"opened","issue":{"url":"https://api.github.com/repos/dmlc/mxnet/issues/1875","repository_url":"https://api.github.com/repos/dmlc/mxnet","labels_url":"https://api.github.com/repos/dmlc/mxnet/issues/1875/labels{/name}","comments_url":"https://api.github.com/repos/dmlc/mxnet/issues/1875/comments","events_url":"https://api.github.com/repos/dmlc/mxnet/issues/1875/events","html_url":"https://github.com/dmlc/mxnet/issues/1875","id":148944224,"number":1875,"title":"run example/rnn/char-rnn.ipynb failed","user":{"login":"wachaong","id":1356861,"avatar_url":"https://avatars.githubusercontent.com/u/1356861?v=3","gravatar_id":"","url":"https://api.github.com/users/wachaong","html_url":"https://github.com/wachaong","followers_url":"https://api.github.com/users/wachaong/followers","following_url":"https://api.github.com/users/wachaong/following{/other_user}","gists_url":"https://api.github.com/users/wachaong/gists{/gist_id}","starred_url":"https://api.github.com/users/wachaong/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/wachaong/subscriptions","organizations_url":"https://api.github.com/users/wachaong/orgs","repos_url":"https://api.github.com/users/wachaong/repos","events_url":"https://api.github.com/users/wachaong/events{/privacy}","received_events_url":"https://api.github.com/users/wachaong/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2016-04-17T11:42:02Z","updated_at":"2016-04-17T11:42:02Z","closed_at":null,"body":"i am new, i got this error here\r\n\r\n07:33:45 INFO:Start training with [gpu(0)]\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\n[19:36:00] src/symbol/static_graph.cc:383: Memory efficient gradient aggregation on... to disable, set MXNET_EXEC_INPLACE_GRAD_SUM_CAP to big number\r\nTraceback (most recent call last):\r\n  File \"char-rnn.py\", line 120, in <module>\r\n    epoch_end_callback=mx.callback.do_checkpoint(\"obama\"))\r\n  File \"/usr/local/lib/python2.7/dist-packages/mxnet-0.5.0-py2.7.egg/mxnet/model.py\", line 774, in fit\r\n    sym_gen=self.sym_gen)\r\n  File \"/usr/local/lib/python2.7/dist-packages/mxnet-0.5.0-py2.7.egg/mxnet/model.py\", line 244, in _train_multi_device\r\n    executor_manager.update_metric(eval_metric, data_batch.label)\r\n  File \"/usr/local/lib/python2.7/dist-packages/mxnet-0.5.0-py2.7.egg/mxnet/executor_manager.py\", line 406, in update_metric\r\n    self.curr_execgrp.update_metric(metric, labels)\r\n  File \"/usr/local/lib/python2.7/dist-packages/mxnet-0.5.0-py2.7.egg/mxnet/executor_manager.py\", line 262, in update_metric\r\n    metric.update(labels_slice, texec.outputs)\r\n  File \"/usr/local/lib/python2.7/dist-packages/mxnet-0.5.0-py2.7.egg/mxnet/metric.py\", line 338, in update\r\n    self.sum_metric += self._feval(label, pred)\r\n  File \"/usr/local/lib/python2.7/dist-packages/mxnet-0.5.0-py2.7.egg/mxnet/metric.py\", line 355, in feval\r\n    return numpy_feval(label, pred)\r\n  File \"char-rnn.py\", line 50, in Perplexity\r\n    loss += -np.log(max(1e-10, pred[i][int(label[i])]))\r\nTypeError: only length-1 arrays can be converted to Python scalars\r\n"}}