Develop Reference

Does Spyder download its own Python with it?

Common issue here: I installed Python and then Spyder, and now when I install packages with "pip install ", Spyder can't find the modules, but if I call Python on the command prompt (using Windows), it finds all installed packages with pip.
I noticed that in Spyder, a new console shows it is running Python 3.7.9, but if I run "python -V" on the command promp, it shows Python 3.9.1 , also for "py -0" and "py -0p" it only shows one installation of Python, namely
>>> py -0p
Installed Pythons found by py Launcher for Windows
-3.9-64 C:\Users\my_name\AppData\Local\Programs\Python\Python39\python.exe *
so what is going on here? Why does Spyder seem to have its own Python version? Is this the reason why packages installed with pip are not communicating with Spyder?

I was facing the same issue as you. I understand your question and the answer to it is yes. However you can change it and use the systems python as well.
Tools -> preferences -> python interpreter -> select "use the following interpreter" and provide is the path to the directory that you have the systems python installed.
Restart spyder and the kernel should then show you the update version

For any library that you want to add that is not included in the default search path of spyder, you need add its path via the PYTHONPATH manager.
Go to Spyder->Tool-> PYTHONPATH manager ->Add Path

Installed Python 3, now my Anaconda environment is messed up

I apologize in advance for my poor vocabulary - I do not know much about environments, paths, and things of the sort. I am on macOS Catalina.
I created a program using Spyder from Anaconda. My program uses packages like pandas and numpy which are built into Anaconda. I used to be able to run the program in Terminal with the command: $ python3 app.py.
However, I recently downloaded Python 3.9.1 from https://www.python.org/downloads/mac-osx/. Ever since then, I have been unable to run the program in Terminal because of missing package errors like
import numpy as np
ModuleNotFoundError: No module named 'numpy'
I went to my applications folder, right clicked on Python 3.9.1, and clicked Move To Trash. This did not solve my problem. I reinstalled Anaconda (I did not uninstall it - just simply installed again), but that also did not solve my problem. I am able to run the program in Spyder (from Anaconda), but I wish to run it in Terminal again.
I believe the solution is simple, but I am not sure what to do. I have tried searching and reading but I am not familiar with the terminology. I think I just need to reset the environment, but I am not sure.

Anaconda is used for creating closed enviorments, so you don't need to thrash your computer with global packages.
Imagine you have 2 different projects. Project A works only on python 3.2 and Project B works on 3.8.
That's where anaconda comes in.Managing enviorments with conda
conda create -n PROJECTA python=3.2
conda create -n PROJECTB python=3.8
Now activate env you wish to work with. For macOS
source activate PROJECTA
Now you should see (PROJECTA) instead of (base)
Now inside this PROJECTA you can install modules you require like
pip install numpy
and when executing .py file
move to dir with your app.py file and
python3 app.py
this will be opened in conda enviorment you created and activated, using modules you installed in this env.
You can still edit py file and execute it through shell, but it will throw errors if you try to run it from IDE without linking project to respected conda enviorment.
If you are using PyCharm Configure a Conda vir env in PyCharm

You must create separate environments for every projects or it will get messed up.
conda create -n name_of_environment python=3.6
You must not delete the python folder into trash rather uninstall it Python 3.9.1 and remove its path from the directory.
In short if you run python from terminal and it is not supporting your Installed anaconda packages . You should use anaconda prompt instead of CMD.
Because your anaconda is not added to path rather then it picks up the python 3.9 you have installed from Python 3.9.1 from https://www.python.org/downloads/mac-osx/. ( This is the python with separate environment then anaconda so it wont detect anaconda packages ).
When you run the cmd and enter python it runs the python that you downloaded and installed rather then Anaconda
At the time of installing anaconda it gives option to add conda variables to path you can select those at installing stage / or add manually

Sometimes Unable to Import NumPy

When I work in Jupyter Notebooks everything works fine, and I can import numpy and pandas successfully. However, when I try to download the script and then run it in an editor such as PyCharm or Atom, I get an import error: no module named numpy, and the same for pandas. How do I fix this? Is this due to the packages being installed in a different location than where I am downloading the code? Everything is installed with Anaconda, and when I try to do ```conda install numpy`` it tells me that all packages have already been installed.

This may be because Pycharm and Atom are using your default python install rather than your anaconda python environment.
You can configure Pycharm to use your conda environment via (https://www.jetbrains.com/help/pycharm/conda-support-creating-conda-virtual-environment.html).

Anaconda uses virtual conda environments to store the Python interpreter and libraries. If this isn't set up in your IDE, it won't see the libraries. This is described in this post: Use Conda environment in pycharm
Check your PyCharm interpreter options: File > Settings > Project > Project Interpreter. Make sure your desired Anaconda interpreter/environment is selected.
If your Anaconda environment isn't selected, click the Project Interpreter drop-down. if you see it there, select it. If not, click Show All... then + (Add) and browse to the Anaconda folder.
This post describes how to set up conda in Atom:
Using anaconda environment in Atom

PyCharm Jupyter got messed up

I'm a newbie to PyCharm and Jupyter. After installing Anaconda, I changed PyCharm project interpreter to Anaconda's python.exe, then I deleted the old virtual env folder where my Jupyter used to run (due to very limited disk space).
Now when I run Jupyter, it shows the following error message:
Error running 'python': Cannot run program "C:\my_work_dir\venv\Scripts\python.exe" (in directory "C:\my_work_dir\python"): CreateProcess error=2, The system cannot find the file specified
I understand the error message means that it cannot find the path. But I don't understand why it keeps looking for the old path while I have changed my project interpreter's path. Please help!

You need to install jupyter for the project interpreter or the venv you use as follow:
pip install jupyter
Note: This is what I suspect is the problem because Anaconda has
all this installed by default but for manual python install you need
to install all this packages(for ipython is required jupyter) in
order to have it work.

Anaconda3 2.4 with python 3.5 installation error (procedure entry not found; Windows 10)

I have just made up my mind to change from python 2.7 to python 3.5 and therefore tried to reinstall Anaconda (64 bit) with the 3.5 environment. When I try to install the package I get several errors in the form of (translation from German, so maybe not exact):
The procedure entry "__telemetry_main_return_trigger" could not be found in the DLL "C:\Anaconda3\pythonw.exe".
and
The procedure entry "__telemetry_main_invoke_trigger" could not be found in the DLL "C:\Anaconda3\python35.dll".
The title of the second error message box still points to pythonw.exe. Both errors appear several times - every time an extraction was completed. The installation progress box reads
[...]
extraction complete.
Execute: "C:\Anaconda3\pythonw.exe" "C:\Anaconda3\Lib_nsis.py" postpkg
After torturing myself through the installation I get the warning
Failed to create Anaconda menus
If I ignore it once gives me my lovely error messages and tells me that
Failed to initialize Anaconda directories
then
Failed to add Anaconda to the system PATH
Of course nothing works, if I dare to use this mess it installs. What might go wrong? On other computers with Windows 10 it works well.
P.S.: An installation of Anaconda2 2.4 with python 2.7 works without any error message, but still is not able to be used (other errors).

Finally I have found the reason. So, if anybody else has this problem:
Here the entry points are an issue as well and Michael Sarahan gives the solution. Install the Visual C++ Redistributable for Visual Studio 2015, which is used by the new version of python, first. After that install the Anaconda-package and it should work like a charm.

You can also use your standard Anaconda installation and just create an environment based on 2.7 / 3.4 etc... Anaconda will download and install all compatible packages from the repository so you have a complete installation.
conda create -n py27 python=2.7 anaconda
conda create -n py34 python=3.4 anaconda
To use the new environment (in Windows), you can point your IDE to the required environment folder:
C:\Anaconda3\envs\py34\python.exe
On the Windows command line, you just need to type:
activate py34
Documentation:
http://conda.pydata.org/docs/py2or3.html
My recommendation would be to reinstall your Anaconda version with Python 2.7 that you previously had working, then just add a new environment for Python 3.x and use that as you need.

I had the same problem, then I Installed "for all users": solved.
Much easier than the links provided for a beginner as I am.

For the problem "Failed to create Anaconda menus", it may because:
This might happen if PATH is too long already. How long is your PATH environment variable? Windows limits this to 1024 characters. There are some workarounds go shorten it here: How do you avoid over-populating the PATH Environment Variable in Windows?
This is other people's question and solution
https://groups.google.com/a/continuum.io/forum/#!topic/anaconda/mjrbE6rKyi8
When I shorted the environment path, it works!

If you are getting errors like:
Failed to create Anaconda menus
Failed to initialize Anaconda directories
Failed to add Anaconda to the system PATH
just ignore them while installation and when installation is done look for the directory "anaconda3" is installed and correct the path accordingly in environment variables path.
In my system, path was set "C:\Anaconda3" but actually it was installed at "C:\ProgramData\Anaconda3". You have to change all 3 path entries for anaconda3 and then try to run "jupyter notebook" in CMD.

If you are using windows, launch the command prompt as administrator and execute the following commands
"C:\ProgramData\Anaconda3\pythonw.exe" -E -s "C:\ProgramData\Anaconda3\Lib_nsis.py" addpath
"C:\ProgramData\Anaconda3\pythonw.exe" -E -s "C:\ProgramData\Anaconda3\Lib_nsis.py" mkdirs
"C:\ProgramData\Anaconda3\pythonw.exe" -E -s "C:\ProgramData\Anaconda3\Lib_nsis.py" mkmenus
Don't forget to change the path to the path in your system. Before running this commands there will not be any Anaconda Navigator app in your start menu. After executing this commands make sure Anaconda Navigator app is available in the start menu.

Change the directory. It works
C:\miniconda3