tensorflow並置錯誤：一個神祕的字符串格式問題

Question

我正試圖在偏置+權重上實現L1規範。爲此，我嘗試將它們連接在一起並採取一種平均值。

即，我有一個偏壓b1（形狀：[1,1]）和重量W1（形狀：[1, xlen]）。於是，我就天真地沿着第一維串連：

self.W1 = tf.Variable(tf.truncated_normal([1, self.xlen], stddev=0.1), name="weight") 
    self.b1 = tf.Variable(tf.constant(0.1, shape=[1, 1]), name="bias") 
    ... 
l1_penalty = tf.reduce_mean(tf.abs(tf.concat(1, (self.W1,self.b1)))) 

但是我得到：

---> 53   l1_penalty = tf.reduce_mean(tf.abs(tf.concat(1, (self.W1,self.b1)))) 
    54 
    55   tot_loss = l2_loss + self.ALPHA * l1_penalty 

/usr/local/lib/python3.4/dist-packages/tensorflow/python/ops/array_ops.py in concat(concat_dim, values, name) 
    304 # TODO(mrry): Change to return values? 
    305 if len(values) == 1: # Degenerate case of one tensor. 
--> 306  return identity(values[0], name=name) 
    307 return gen_array_ops._concat(concat_dim=concat_dim, 
    308        values=values, 

/usr/local/lib/python3.4/dist-packages/tensorflow/python/ops/gen_array_ops.py in identity(input, name) 
    313  A `Tensor`. Has the same type as `input`. 
    314 """ 
--> 315 return _op_def_lib.apply_op("Identity", input=input, name=name) 
    316 
    317 

/usr/local/lib/python3.4/dist-packages/tensorflow/python/ops/op_def_library.py in apply_op(self, op_type_name, g, name, **keywords) 
    419    values = ops.convert_to_tensor(
    420     values, name=input_arg.name, dtype=dtype, 
--> 421     as_ref=input_arg.is_ref) 
    422   except ValueError: 
    423    # What type does convert_to_tensor think it has? 

/usr/local/lib/python3.4/dist-packages/tensorflow/python/framework/ops.py in convert_to_tensor(value, dtype, name, as_ref) 
    522  for base_type, conversion_func in funcs_at_priority: 
    523  if isinstance(value, base_type): 
--> 524   ret = conversion_func(value, dtype=dtype, name=name, as_ref=as_ref) 
    525   if not isinstance(ret, Tensor): 
    526   raise RuntimeError(

/usr/local/lib/python3.4/dist-packages/tensorflow/python/ops/constant_op.py in _constant_tensor_conversion_function(v, dtype, name, as_ref) 
    176           as_ref=False): 
    177 _ = as_ref 
--> 178 return constant(v, dtype=dtype, name=name) 
    179 
    180 

/usr/local/lib/python3.4/dist-packages/tensorflow/python/ops/constant_op.py in constant(value, dtype, shape, name) 
    159 tensor_value = attr_value_pb2.AttrValue() 
    160 tensor_value.tensor.CopyFrom(
--> 161  tensor_util.make_tensor_proto(value, dtype=dtype, shape=shape)) 
    162 dtype_value = attr_value_pb2.AttrValue(type=tensor_value.tensor.dtype) 
    163 const_tensor = g.create_op(

/usr/local/lib/python3.4/dist-packages/tensorflow/python/framework/tensor_util.py in make_tensor_proto(values, dtype, shape) 
    382 if numpy_dtype == dtypes.string and not isinstance(values, np.ndarray): 
    383  proto_values = _FlattenToStrings(values) 
--> 384  tensor_proto.string_val.extend([compat.as_bytes(x) for x in proto_values]) 
    385  return tensor_proto 
    386 

/usr/local/lib/python3.4/dist-packages/tensorflow/python/framework/tensor_util.py in <listcomp>(.0) 
    382 if numpy_dtype == dtypes.string and not isinstance(values, np.ndarray): 
    383  proto_values = _FlattenToStrings(values) 
--> 384  tensor_proto.string_val.extend([compat.as_bytes(x) for x in proto_values]) 
    385  return tensor_proto 
    386 

/usr/local/lib/python3.4/dist-packages/tensorflow/python/util/compat.py in as_bytes(bytes_or_text) 
    41  return bytes_or_text 
    42 else: 
---> 43  raise TypeError('Expected binary or unicode string, got %r' % bytes_or_text) 
    44 
    45 

TypeError: not all arguments converted during string formatting 

添加一個名稱參數沒有幫助。

作爲替代，tf.reduce_sum與我一起工作，但tf.concat有什麼問題？

Answer 1

該問題似乎是由this line of the tf.concat() implementation上的一個錯誤引起的。目前—和與大多數其他可變參數TensorFlow運營商— tf.concat()只接受清單張量，並且不處理元組正確。如果你改變你的代碼下面，它應該工作：

l1_penalty = tf.reduce_mean(tf.abs(tf.concat(1, [self.W1, self.b1]))) 

在此期間，我會解決此問題，並把它提交上游，因此，它在下一版本處理。