我已经在Jupyter Notebook中编写了以下代码，该代码在Tensorflow中执行线性回归：
import tensorflow as tf
import numpy as np
import pandas as pd
from sklearn.datasets import load_boston
import matplotlib.pyplot as plt
boston=load_boston()
type(boston)
boston.feature_names
bd=pd.DataFrame(data=boston.data,columns=boston.feature_names)
bd['Price']=pd.DataFrame(data=boston.target)
np.random.shuffle(bd.values)
W0=tf.Variable(0.0000000000003)
W1=tf.Variable(0.000000000002)
b=tf.Variable(0.0000000000001)
#print(bd.shape[1])
tf.summary.histogram('Weights', W0)
tf.summary.histogram('Weights', W1)
tf.summary.histogram('Biases', b)
dataset_input=bd.iloc[:, 0 : bd.shape[1]-1];
#dataset_input.head(2)
dataset_output=bd.iloc[:, bd.shape[1]-1]
dataset_output=dataset_output.values
dataset_output=dataset_output.reshape((bd.shape[0],1)) #converted (506,) to (506,1) because in pandas
#the shape was not changing and it was needed later in feed_dict
dataset_input=dataset_input.values #only dataset_input is in DataFrame form and converting it into np.ndarray
# ADDED
dataset_input = np.array(dataset_input, dtype=np.float32)
# ADDED
dataset_output = np.array(dataset_output, dtype=np.float32)
X=tf.placeholder(tf.float32, shape=(None,bd.shape[1]-1))
Y=tf.placeholder(tf.float32, shape=(None,1))
Y_=W0*X*X + W1*X + b
#Y_pred = tf.add(tf.multiply(tf.pow(X, pow_i), W), Y_pred)
print(X.shape)
print(Y.shape)
loss=tf.reduce_mean(tf.square(Y_-Y))
tf.summary.scalar('loss',loss)
optimizer=tf.train.GradientDescentOptimizer(0.0000000000001)
train=optimizer.minimize(loss)
init=tf.global_variables_initializer()#tf.global_variables_initializer()#tf.initialize_all_variables()
sess=tf.Session()
sess.run(init)
wb_=[]
with tf.Session() as sess:
summary_merge = tf.summary.merge_all()
writer=tf.summary.FileWriter("Users/ajay/Desktop",sess.graph)
epochs=6
sess.run(init)
for i in range(epochs):
s_mer=sess.run(summary_merge,feed_dict={X: dataset_input, Y: dataset_output}) #ERROR________ERROR
sess.run(train,feed_dict={X:dataset_input,Y:dataset_output})
#CHANGED
print("loss",sess.run(loss, feed_dict={X:dataset_input,Y:dataset_output}))
#sess.run(loss, feed_dict={X:dataset_input,Y:dataset_output})
writer.add_summary(s_mer,i)
tf.summary.histogram(name="loss",values=loss)
if(i%5==0):
print(i, sess.run([W0,W1,b]))
wb_.append(sess.run([W0,W1,b]))
print(writer.get_logdir())
print(writer.close())
它给出了以下错误：
(?, 13)
(?, 1)
---------------------------------------------------------------------------
InvalidArgumentError Traceback (most recent call last)
~/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/client/session.py in _do_call(self, fn, *args)
1038 try:
-> 1039 return fn(*args)
1040 except errors.OpError as e:
~/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/client/session.py in _run_fn(session, feed_dict, fetch_list, target_list, options, run_metadata)
1020 feed_dict, fetch_list, target_list,
-> 1021 status, run_metadata)
1022
~/anaconda3/envs/Tensorflow/lib/python3.6/contextlib.py in __exit__(self, type, value, traceback)
87 try:
---> 88 next(self.gen)
89 except StopIteration:
~/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/framework/errors_impl.py in raise_exception_on_not_ok_status()
465 compat.as_text(pywrap_tensorflow.TF_Message(status)),
--> 466 pywrap_tensorflow.TF_GetCode(status))
467 finally:
InvalidArgumentError: You must feed a value for placeholder tensor 'Placeholder' with dtype float
[[Node: Placeholder = Placeholder[dtype=DT_FLOAT, shape=[], _device="/job:localhost/replica:0/task:0/cpu:0"]()]]
During handling of the above exception, another exception occurred:
InvalidArgumentError Traceback (most recent call last)
<ipython-input-8-fdf4bc1529e6> in <module>()
73
74 for i in range(epochs):
---> 75 s_mer=sess.run(summary_merge,feed_dict={X: dataset_input, Y: dataset_output}) #ERROR________ERROR
76 sess.run(train,feed_dict={X:dataset_input,Y:dataset_output})
77
~/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/client/session.py in run(self, fetches, feed_dict, options, run_metadata)
776 try:
777 result = self._run(None, fetches, feed_dict, options_ptr,
--> 778 run_metadata_ptr)
779 if run_metadata:
780 proto_data = tf_session.TF_GetBuffer(run_metadata_ptr)
~/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/client/session.py in _run(self, handle, fetches, feed_dict, options, run_metadata)
980 if final_fetches or final_targets:
981 results = self._do_run(handle, final_targets, final_fetches,
--> 982 feed_dict_string, options, run_metadata)
983 else:
984 results = []
~/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/client/session.py in _do_run(self, handle, target_list, fetch_list, feed_dict, options, run_metadata)
1030 if handle is None:
1031 return self._do_call(_run_fn, self._session, feed_dict, fetch_list,
-> 1032 target_list, options, run_metadata)
1033 else:
1034 return self._do_call(_prun_fn, self._session, handle, feed_dict,
~/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/client/session.py in _do_call(self, fn, *args)
1050 except KeyError:
1051 pass
-> 1052 raise type(e)(node_def, op, message)
1053
1054 def _extend_graph(self):
InvalidArgumentError: You must feed a value for placeholder tensor 'Placeholder' with dtype float
[[Node: Placeholder = Placeholder[dtype=DT_FLOAT, shape=[], _device="/job:localhost/replica:0/task:0/cpu:0"]()]]
Caused by op 'Placeholder', defined at:
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/runpy.py", line 193, in _run_module_as_main
"__main__", mod_spec)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/runpy.py", line 85, in _run_code
exec(code, run_globals)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/ipykernel_launcher.py", line 16, in <module>
app.launch_new_instance()
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/traitlets/config/application.py", line 658, in launch_instance
app.start()
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/ipykernel/kernelapp.py", line 486, in start
self.io_loop.start()
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tornado/platform/asyncio.py", line 127, in start
self.asyncio_loop.run_forever()
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/asyncio/base_events.py", line 421, in run_forever
self._run_once()
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/asyncio/base_events.py", line 1431, in _run_once
handle._run()
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/asyncio/events.py", line 145, in _run
self._callback(*self._args)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tornado/platform/asyncio.py", line 117, in _handle_events
handler_func(fileobj, events)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tornado/stack_context.py", line 276, in null_wrapper
return fn(*args, **kwargs)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/zmq/eventloop/zmqstream.py", line 450, in _handle_events
self._handle_recv()
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/zmq/eventloop/zmqstream.py", line 480, in _handle_recv
self._run_callback(callback, msg)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/zmq/eventloop/zmqstream.py", line 432, in _run_callback
callback(*args, **kwargs)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tornado/stack_context.py", line 276, in null_wrapper
return fn(*args, **kwargs)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/ipykernel/kernelbase.py", line 283, in dispatcher
return self.dispatch_shell(stream, msg)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/ipykernel/kernelbase.py", line 233, in dispatch_shell
handler(stream, idents, msg)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/ipykernel/kernelbase.py", line 399, in execute_request
user_expressions, allow_stdin)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/ipykernel/ipkernel.py", line 208, in do_execute
res = shell.run_cell(code, store_history=store_history, silent=silent)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/ipykernel/zmqshell.py", line 537, in run_cell
return super(ZMQInteractiveShell, self).run_cell(*args, **kwargs)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/IPython/core/interactiveshell.py", line 2662, in run_cell
raw_cell, store_history, silent, shell_futures)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/IPython/core/interactiveshell.py", line 2785, in _run_cell
interactivity=interactivity, compiler=compiler, result=result)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/IPython/core/interactiveshell.py", line 2903, in run_ast_nodes
if self.run_code(code, result):
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/IPython/core/interactiveshell.py", line 2963, in run_code
exec(code_obj, self.user_global_ns, self.user_ns)
File "<ipython-input-1-67ab0a0aaf1a>", line 44, in <module>
X=tf.placeholder(tf.float32, shape=(None,bd.shape[1]-1))
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/ops/array_ops.py", line 1507, in placeholder
name=name)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/ops/gen_array_ops.py", line 1997, in _placeholder
name=name)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/framework/op_def_library.py", line 768, in apply_op
op_def=op_def)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 2336, in create_op
original_op=self._default_original_op, op_def=op_def)
File "/Users/ajay/anaconda3/envs/Tensorflow/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 1228, in __init__
self._traceback = _extract_stack()
InvalidArgumentError (see above for traceback): You must feed a value for placeholder tensor 'Placeholder' with dtype float
[[Node: Placeholder = Placeholder[dtype=DT_FLOAT, shape=[], _device="/job:localhost/replica:0/task:0/cpu:0"]()]]
但是当我在Terminal中运行它时，它会给出以下输出：
MacBook-Air:Desktop ajay$ python3 LR.py
/anaconda3/lib/python3.6/site-packages/h5py/__init__.py:36: FutureWarning: Conversion of the second argument of issubdtype from `float` to `np.floating` is deprecated. In future, it will be treated as `np.float64 == np.dtype(float).type`.
from ._conv import register_converters as _register_converters
(?, 13)
(?, 1)
2018-08-16 13:40:30.387637: I tensorflow/core/platform/cpu_feature_guard.cc:141] Your CPU supports instructions that this TensorFlow binary was not compiled to use: AVX2 FMA
loss 592.02905
0 [1.08720556e-07, 3.084597e-10, 4.6065617e-12]
Users/ajay/Desktop
None
loss 591.9113
Users/ajay/Desktop
None
loss 591.7939
Users/ajay/Desktop
None
loss 591.67664
Users/ajay/Desktop
None
loss 591.5597
Users/ajay/Desktop
None
loss 591.44293
5 [6.502434e-07, 1.8367864e-09, 2.7130916e-11]
Users/ajay/Desktop
None
我的终端机是否忽略了有关PlaceHolder的其他内容？ 我无法识别与“占位符”相关的错误。
任何人都可以向我解释如何识别它们以及它们何时最有可能发生？
此外，此代码中是否有与数据类型相关的任何内容
/anaconda3/lib/python3.6/site-packages/h5py/__init__.py:36: FutureWarning: Conversion of the second argument of issubdtype from `float` to `np.floating` is deprecated. In future, it will be treated as `np.float64 == np.dtype(float).type`.
答案 0 :(得分：1)
我认为您可以在Jupyter Notebook中的代码的第一行添加tf.reset_default_graph()并进行检查。