Jupyter Notebook运行代码无反应问题及解决方法

Jupyter Notebook运行代码无反应

在学习人脸识别知识的过程中需要用到Anaconda 、Jupyter Notebook.

我在启动Jupyter Notebook后，新建代码运行无反应。

从页面上也观察不出来是什么问题，后来在Anaconda Pormpt中启动Jupyter Notebook，我一开始还以为是自动启动的，傻傻的等它自动运行。。。

结果是在浏览器中操作，命令行中才会跑模块的运行情况。

要在浏览器中shift+enter执行代码片段，后台包这个错误。

 
(tensorflow) C:\Users\admin>jupyter notebook
[I 15:55:33.979 NotebookApp] The port 8888 is already in use, trying another port.
[I 15:55:34.011 NotebookApp] The port 8889 is already in use, trying another port.
[I 15:55:34.130 NotebookApp] Serving notebooks from local directory: C:\Users\admin
[I 15:55:34.131 NotebookApp] The Jupyter Notebook is running at:
[I 15:55:34.137 NotebookApp] http://localhost:8890/?token=7d8aff641154f969e61dec8ebd511d98849f08829e440fe0
[I 15:55:34.139 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).
[C 15:55:34.220 NotebookApp]
 
    To access the notebook, open this file in a browser:
        file:///C:/Users/admin/AppData/Roaming/jupyter/runtime/nbserver-24428-open.html
    Or copy and paste one of these URLs:
        http://localhost:8890/?token=7d8aff641154f969e61dec8ebd511d98849f08829e440fe0
Traceback (most recent call last):
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\tornado\ioloop.py", line 888, in start
    handler_func(fd_obj, events)
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\tornado\stack_context.py", line 277, in null_wrapper
    return fn(*args, **kwargs)
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\zmq\eventloop\zmqstream.py", line 450, in _handle_events
    self._handle_recv()
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\zmq\eventloop\zmqstream.py", line 480, in _handle_recv
    self._run_callback(callback, msg)
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\zmq\eventloop\zmqstream.py", line 432, in _run_callback
    callback(*args, **kwargs)
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\tornado\stack_context.py", line 277, in null_wrapper
    return fn(*args, **kwargs)
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\ipykernel\kernelbase.py", line 283, in dispatcher
    return self.dispatch_shell(stream, msg)
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\ipykernel\kernelbase.py", line 233, in dispatch_shell
    self.pre_handler_hook()
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\site-packages\ipykernel\kernelbase.py", line 248, in pre_handler_hook
    self.saved_sigint_handler = signal(SIGINT, default_int_handler)
  File "C:\Users\admin\Anaconda3\envs\tensorflow\lib\signal.py", line 47, in signal
    handler = _signal.signal(_enum_to_int(signalnum), _enum_to_int(handler))
ValueError: signal only works in main thread
[IPKernelApp] WARNING | Parent appears to have exited, shutting down.

然后参考https://www.jb51.net/article/271651.htm  解决。

(tensorflow) C:\Users\admin>pip install "pyzmq==17.0.0" "ipykernel==4.8.2"
Collecting pyzmq==17.0.0
  Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ReadTimeoutError("HTTPSConnectionPool(host='pypi.org', port=443): Read timed out. (read timeout=15)",)': /simple/pyzmq/
  Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ReadTimeoutError("HTTPSConnectionPool(host='pypi.org', port=443): Read timed out. (read timeout=15)",)': /simple/pyzmq/
  Downloading https://files.pythonhosted.org/packages/27/0b/a275f30738a014dc25443d2f45156ca739991df581fdaa40aa19df6c4f86/pyzmq-17.0.0-cp36-cp36m-win_amd64.whl (944kB)
    100％ |████████████████████████████████| 952kB 49kB/s
Collecting ipykernel==4.8.2
  Downloading https://files.pythonhosted.org/packages/ab/3f/cd624c835aa3336a9110d0a99e15070f343b881b7d651ab1375ef226a3ac/ipykernel-4.8.2-py3-none-any.whl (108kB)
    100％ |████████████████████████████████| 112kB 58kB/s
Requirement already satisfied: ipython>=4.0.0 in c:\users\admin\anaconda3\envs\tensorflow\lib\site-packages (from ipykernel==4.8.2) (6.1.0)
Requirement already satisfied: tornado>=4.0 in c:\users\admin\anaconda3\envs\tensorflow\lib\site-packages (from ipykernel==4.8.2) (4.5.2)
Requirement already satisfied: traitlets>=4.1.0 in c:\users\admin\anaconda3\envs\tensorflow\lib\site-packages (from ipykernel==4.8.2) (4.3.2)
Requirement already satisfied: jupyter-client in c:\users\admin\anaconda3\envs\tensorflow\lib\site-packages (from ipykernel==4.8.2) (5.2.4)
Requirement already satisfied: jupyter-core in c:\users\admin\anaconda3\envs\tensorflow\lib\site-packages (from jupyter-client->ipykernel==4.8.2) (4.4.0)
Requirement already satisfied: python-dateutil>=2.1 in c:\users\admin\anaconda3\envs\tensorflow\lib\site-packages (from jupyter-client->ipykernel==4.8.2) (2.6.1)
Requirement already satisfied: six>=1.5 in c:\users\admin\anaconda3\envs\tensorflow\lib\site-packages (from python-dateutil>=2.1->jupyter-client->ipykernel==4.8.2) (1.10.0)
Installing collected packages: pyzmq, ipykernel
  Found existing installation: pyzmq 17.1.2
    Uninstalling pyzmq-17.1.2:
      Successfully uninstalled pyzmq-17.1.2
  Found existing installation: ipykernel 4.6.1
Cannot uninstall 'ipykernel'. It is a distutils installed project and thus we cannot accurately determine which files belong to it which would lead to only a partial uninstall.

安装时报错，ipykernel不能卸载，我也尝试过重新装，一直报这个错误。索性没管它，直接再浏览器中重新运行就可以正常运行了。

这是修复后的运行效果。

jupyter notebook 某个cell 一直在运行

近期调试程序，发现一简单的代码一直在运行，很长时间不终止，代码如下：

whole_df=pd.read_csv(r'./train.csv')
 
community=whole_df['COMMUNITY_ID'].unique()
 
for community_id in community:
 
    temp=check_result[check_result['COMMUNITY_ID']==community_id]
 
    start=temp.index.tolist()[0]
 
    delanomaly_test(temp,start) 

其中delanomaly_test 是对测试数据进行处理异常值的函数，函数里有对形参temp进行赋值的操作，而temp 是whole_df的切片，执行后，出现了很多提示：

/usr/local/python3/lib/python3.6/site-packages/pandas/core/indexing.py:1763: SettingWithCopyWarning:

A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead

See the caveats in the documentation: https://pandas.pydata.org/pandas-docs/stable/user_guide/indexing.html#returning-a-view-versus-a-copy

一大串的全是提示，而且还一直扩展向下，过了10分钟，不再出现提示，但是这段cell 执行符号里显示‘*’，为一直在执行，本身数据量不大，community 为200个,check_result为8万条，应该2、3分钟就结束了但是又过5分钟还是‘*’号，点‘Interrupt the kernel ’也是很长时间没反应。用写标准输出+写文件的方式测试下：

whole_df=pd.read_csv(r'./train.csv')
 
community=whole_df['COMMUNITY_ID'].unique()
filename='proeceeing.txt'
 
with open(file_name,'w+') as f:
 
    f.write(file_name)
 
w=0 #进度的变量
 
for community_id in community:
 
    if w％50==0:
 
        print('w=％s' ％str(w)) #打印至标准输出
 
        f=open(file_name,'a')
 
        f.write('\n     '+str(w)+':')#写入文件
 
        f.write(time.strftime('％Y-％m-％d ％H:％M:％S',time.localtime(time.time())))  
 
        f.close()
 
    temp=check_result[check_result['COMMUNITY_ID']==community_id]
 
    start=temp.index.tolist()[0]
 
    delanomaly_test(temp,start)
 
    w=w+1
print('w=％s' ％str(w)) #打印至标准输出
 
f=open(file_name,'a')
 
print('w=％s' ％str(w))
 
f.write('\n     '+str(w)+':') #写入文件
 
f.write(time.strftime('％Y-％m-％d ％H:％M:％S',time.localtime(time.time())))
 
f.write('\n check_result executed ')
 
f.close()

执行后，文件内容如下：

processing.txt
     0:2021-08-25 21:14:38
     50:2021-08-25 21:14:43
     100:2021-08-25 21:14:49
     150:2021-08-25 21:14:54
     200:2021-08-25 21:15:00
 check_result executed 

看来这段代码在一分钟之内已经执行完毕，再看标准输出，还是有很多之前的提示，同时标示进度的w值里，只发现了三条：

w=0

w=50

w=100

再向后就只有提示，再向后提示也终止了

因此这段代码一直执行的可能原因是短时间内写大量内容至标准输出，标准输出缓冲区满，无法打印提示和之后的内容，但程序实际已执行完毕。最后删除delanomaly_test 函数里的切片赋值语句，发现这段代码很快结束，至此问题有三个：切片不可直接赋值，标准输出不可靠，每个提示都要细看

来源：https://blog.csdn.net/qq_34733907/article/details/88822786