I can run my app from the console that there is in pyCharm but If I try to run my app from a shell my app doesn't find "pymysql" module.
The module is installed in my project in a virtual environment. You can see in the next image how is installed this module.
And If try to run my app from the shell I've got this error:
I'm using python3.
What am I doing wrong? Is there any easy way to access to the module?
There are several ways:
activate virtual env: source venv/bin/activate.
directly use specific python: venv/bin/python main.py
Surely you can temporarily add venv/bin to your PATH, that's almost the same as the first option: export PATH=full/path/to/bin:$PATH
Generally I recommend the first option. But sometimes you may want to use the second one. For example, you want to use this python in a crontab script.
Having some weird troubles installing python modules on my work computer (read: no admin/root rights), I'm using 2.7.5. I downloaded and unpacked the tarball and ran 'setup.py', but it had no effect: When I open the python shell, it can't find the module (this specific one is fuzzywuzzy). However, if I right click -> edit with IDLE the setup.py, and then run the shell from that file, it loads and works perfectly fine. Or, if I then open a new file from that shell, use the module and run it, it works fine. -__-
I've tried using:
import sys
sys.path.append('path here')
to append the location where the module is installed, but this doesn't help, nor does the path stay in the sys.path list when I close/reopen the shell.
This is actually driving me insane. Can anyone help? I'm relatively new to programming and python.
The best and easy way provided by python to install/uninstall packages is to use PIP.
use this
python -m pip install packagename==version
same way to uninstall
python -m pip uninstall packagename==version
if you are using windows you need to set path variable first usually python file will be in path C:\Python27 to set path variable
PATH=%PATH%;C:\Python27;
I have a full python installation with files in /usr/local/, but also have one that I compiled from source sitting in ~/python_dist. If I look at sys.path on each interpreter I see that they indeed import from different libraries.
Currently I can run $ PYTHONPATH=~/other_py_libs ~/python_dist/bin/python to invoke the custom interpreter with some other modules available in the path. However, I don't want permanently change the global PYTHONPATH variable.
How can I permanently change the python path for only one specific python install?
The easiest way to do this is to use a virtualenv (manage with virtualenvwrapper). With virtual environments you can set up different, isolated python environments (kind of like little python playgrounds). Switching between them (with the help of virtualenvwrapper) is as easy as typing workon envname. You don't have to worry about switching the PYTHONPATH around, and you can direct scripts to use a specific environment simply by running them with the python install in that environment, e.g. using #! /home/myname/.virtualenvs/envname/bin python.
I'm trying to run a script that launches, amongst other things, a python script. I get a ImportError: No module named ..., however, if I launch ipython and import the same module in the same way through the interpreter, the module is accepted.
What's going on, and how can I fix it? I've tried to understand how python uses PYTHONPATH but I'm thoroughly confused. Any help would greatly appreciated.
This issue arises due to the ways in which the command line IPython interpreter uses your current path vs. the way a separate process does (be it an IPython notebook, external process, etc). IPython will look for modules to import that are not only found in your sys.path, but also on your current working directory. When starting an interpreter from the command line, the current directory you're operating in is the same one you started ipython in. If you run
import os
os.getcwd()
you'll see this is true.
However, let's say you're using an ipython notebook, run os.getcwd() and your current working directory is instead the folder in which you told the notebook to operate from in your ipython_notebook_config.py file (typically using the c.NotebookManager.notebook_dir setting).
The solution is to provide the python interpreter with the path-to-your-module. The simplest solution is to append that path to your sys.path list. In your notebook, first try:
import sys
sys.path.append('my/path/to/module/folder')
import module_of_interest
If that doesn't work, you've got a different problem on your hands unrelated to path-to-import and you should provide more info about your problem.
The better (and more permanent) way to solve this is to set your PYTHONPATH, which provides the interpreter with additional directories look in for python packages/modules. Editing or setting the PYTHONPATH as a global var is os dependent, and is discussed in detail here for Unix or Windows.
Just create an empty python file with the name __init__.py under the folder which showing error, while you running the python project.
Make sure they are both using the same interpreter. This happened to me on Ubuntu:
$ ipython3 -c 'import sys; print(sys.version)'
3.4.2 (default, Jun 19 2015, 11:34:49) \n[GCC 4.9.1]
$ python3 -c 'import sys; print(sys.version)'
3.3.0 (default, Nov 27 2012, 12:11:06) \n[GCC 4.6.3]
And sys.path was different between the two interpreters. To fix it, I removed Python 3.3.
The main reason is the sys.paths of Python and IPython are different.
Please refer to lucypark link, the solution works in my case. It happen when install opencv by
conda install opencv
And got import error in iPython, There are three steps to solve this issue:
import cv2
ImportError: ...
1. Check path in Python and iPython with following command
import sys
sys.path
You will find different result from Python and Jupyter. Second step, just use sys.path.append to fix the missed path by try-and-error.
2. Temporary solution
In iPython:
import sys
sys.path.append('/home/osboxes/miniconda2/lib/python2.7/site-packages')
import cv2
the ImportError:.. issue solved
3. Permanent solution
Create an iPython profile and set initial append:
In bash shell:
ipython profile create
... CHECK the path prompted , and edit the prompted config file like my case
vi /home/osboxes/.ipython/profile_default/ipython_kernel_config.py
In vi, append to the file:
c.InteractiveShellApp.exec_lines = [
'import sys; sys.path.append("/home/osboxes/miniconda2/lib/python2.7/site-packages")'
]
DONE
Doing sys.path.append('my-path-to-module-folder') will work, but to avoid having to do this in IPython every time you want to use the module, you can add export PYTHONPATH="my-path-to-module-folder:$PYTHONPATH" to your ~/.bash_profile file.
This is how I fixed it:
import os
import sys
module_path = os.path.abspath(os.getcwd() + '\\..')
if module_path not in sys.path:
sys.path.append(module_path)
Before installing ipython, I installed modules through easy_install; say sudo easy_install mechanize.
After installing ipython, I had to re-run easy_install for ipython to recognize the modules.
If you are running it from command line, sometimes python interpreter is not aware of the path where to look for modules.
Below is the directory structure of my project:
/project/apps/..
/project/tests/..
I was running below command:
>> cd project
>> python tests/my_test.py
After running above command i got below error
no module named lib
lib was imported in my_test.py
i printed sys.path and figured out that path of project i am working on is not available in sys.path list
i added below code at the start of my script my_test.py .
import sys
import os
module_path = os.path.abspath(os.getcwd())
if module_path not in sys.path:
sys.path.append(module_path)
I am not sure if it is a good way of solving it but yeah it did work for me.
I have found that the solution to this problem was extensively documented here:
https://jakevdp.github.io/blog/2017/12/05/installing-python-packages-from-jupyter/
Basically, you must install the packages within the Jupyter environment, issuing shell commands like:
!{sys.executable} -m pip install numpy
Please check the above link for an authoritative full answer.
This kind of errors occurs most probably due to python version conflicts. For example, if your application runs only on python 3 and you got python 2 as well, then it's better to specify which version to use.
For example use
python3 .....
instead of
python
Had a similar problem, fixed it by calling python3 instead of python, my modules were in Python3.5.
This problem occurs due to the different versioning - e.g. if the Python installed on your machine is installed in a folder called path_to_lib/python3.6 but your notebook is running in Python 3 - the spacing in the naming matters!
How to solve it?
When creating a new jupyter notebook, just choose the Python with the same versioning as yours (watch out for spaces!). See the attached image.
I found yet another source of this discrepancy:
I have ipython installed both locally and in commonly in virtualenvs. My problem was that, inside a newly made virtualenv with ipython, the system ipython was picked up, which was a different version than the python and ipython in the virtualenv (a 2.7.x vs. a 3.5.x), and hilarity ensued.
I think the smart thing to do whenever installing something that will have a binary in yourvirtualenv/bin is to immediately run rehash or similar for whatever shell you are using so that the correct python/ipython gets picked up. (Gotta check if there are suitable pip post-install hooks...)
Solution without scripting:
Open Spyder -> Tools -> PYTHONPATH manager
Add Python paths by clicking "Add Path".
E.g: 'C:\Users\User\AppData\Local\Programs\Python\Python37\Lib\site-packages'
Click "Synchronize..." to allow other programs (e.g. Jupyter Notebook) use the pythonpaths set in step 2.
Restart Jupyter if it is open
This is probably caused by different python versions installed on your system, i.e. python2 or python3.
Run command $ pip --version and $ pip3 --version to check which pip is from at Python 3x. E.g. you should see version information like below:
pip 19.0.3 from /usr/local/lib/python3.7/site-packages/pip (python 3.7)
Then run the example.py script with below command
$ python3 example.py
Happened to me with the directory utils. I was trying to import this directory as:
from utils import somefile
utils is already a package in python. Just change your directory name to something different and it should work just fine.
This answer applies to this question if
You don't want to change your code
You don't want to change PYTHONPATH permanently
Temporarily modify PYTHONPATH
path below can be relative
PYTHONPATH=/path/to/dir python script.py
import sys
sys.path.append('/Users/{user}/Library/Python/3.7/lib/python/site-packages')
import ta
If anyone comes across this issue using conda with Jupyter Notebook in MSVS Code, the solution is to make sure you're using the correct kernel. The kernel is in a box in the top right corner of the interface and looks like this:
I pointed mine to the version of Python that also matched my application path -- problem solved!
This is what worked for me: I just changed my working directory inside my notebook
import os
os.chdir("my/path/to/module")
os.getcwd()
I have a similar issued with my Jupyter Lab setup which I resolved by checking the Jupyter Lab log on opening. This informed me that the virtual environment (pipenv) couldn't locate the Jupyter Lab so it used a shared version (from an earlier installation of Python).
I created a requirements.txt and discovered I hadn't installed Jupyter Lab in this new environment. Installing it resolved the import error.
Remove pathlib and reinstall it. Delete the pathlib in sitepackages folder and reinstall the pathlib package by using pip command:
pip install pathlib
this might be a very simple question but I need your help. I work in a network and I cannot install the programs I want. Anyway, I need to use another version of python, which is installed in the directory /new_version/.
Now, when I type "python" in a shell (I use bash) the command point to the version of python installed in the machine I'm working with. I'd love that when I type "python" this command point to the /new_version/ which I've installed. It would be also better if I can call this "new version" with another command, i.e. python2.
I tried changing the PYTHONPATH in the .bashrc but it didn't work.
alias newpython="/path/to/your/new_version/python"
Add this to your .bashrc, you can then start the new python with newpython and the standard one with python.
Add the line
export PATH=/new_version/:$PATH
to your ~/.bashrc (or ~/.bash_profile) file. Then, whenever you run python, it will find the new version first in your PATH. Note this is PATH, not PYTHONPATH. See the comment by #Aaron.
Edit: Only do it this way if you want python to point to the new version. Use an alias as #cularis suggested if you want to call it something different, or make a symlink with:
ln -s /new_version/python /path/to/a/dir/you/add/to/your/path/newpython
Install virtualenv. With this you can easily set up different Python versions like that:
virtualenv -p /new_version/bin/python
Also, virtualenv enables you to easily install other Python packages via pip install.
And finally, there's a package called tox which can automate testing with different Python versions...