[Installation] Moving install discussion from Issue #967

[asoplata]

Describe the problem to us.

(Hey @dikshant182004 , I'm moving the discussion on installation problems from the comments in Issue #967 to here, since they are not relevant to that Issue.)

Original starter comment:

hii @asoplata ,i am so sorry for the late reply as i was indulge in college exams ,so was not able to make any contribution .now i have started looking this issue but i am unable to install neuron for checking my tests .i am not able to understand why this is happening as i have installed neuron in my local machine but not able to use in my virtual env ,i have tried many things to use neuron but was not able to reach the starting point .so i would be grateful if u can guide me .

What steps did you follow to install?

N/A

Error message

N/A

OS

Windows

[asoplata]

Sure Dikshant. Please make sure you read our Installation guide carefully. Are you on Windows, or are you on Mac/Linux? Which platform you are on affects how you are supposed to install NEURON on your machine.

[asoplata]

@dikshant182004 wrote:

yeah i have read your installation guide and i am on windows . in that i am not able to find how to install neuron in my virtual env rather than local machine

[asoplata]

I wrote:

The installation on Windows is a bit different (I am currently working on updating the install documentation, actually). Unlike Mac or Linux, you should not install NEURON directly into your virtual environment. Instead, do the following:

First, download and install a Windows binary for NEURON from here https://nrn.readthedocs.io/en/latest/install/install_instructions.html#windows . This will install NEURON "system-wide".
After you have done that, then create a virtual environment and enter it; make sure you open a new Command or Terminal window instead of using a pre-existing one.
Then, pip install -e '.[dev]' from the directory where you have downloaded the source code.

This should get your install into a working development state. Your virtual environment should be able to find the system-wide NEURON install automatically.

Please note, however, that we do not support MPI usage on Windows (including use of MPIBackend). When you run make test, the tests that require MPI should be automatically skipped

[asoplata]

@dikshant182004 wrote:

it is showing this error
Traceback (most recent call last):
File "J:\HNN\myenv\lib\site-packages\neuron_init_.py", line 148, in
from . import hoc
ImportError: DLL load failed while importing hoc: The specified module could not be found.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "", line 1, in
File "J:\HNN\myenv\lib\site-packages\neuron_init_.py", line 150, in
import neuron.hoc
ImportError: DLL load failed while importing hoc: The specified module could not be found.

i am encountered with this issue .i have tried many ways to solve this like i have switched to python 3.9 ,installed neuron multiple times to check is there any installation or not but still it is showing this i think that at the time of installation hoc folder is going missing dont know why previously it was there but then i reinstalled it it is not coming .plz have a look at thi s

[asoplata]

@dikshant182004 wrote

plz guide me resolving this issue as i have tried every possible ways but not able to reach the solution

[asoplata]

I wrote:

Hello Dikshant, I will try to provide more feedback later today. In the meantime, judging from the traceback, you appear to be using an installation of Neuron from inside your virtual environment, instead of the system-wide Neuron. Try running pip uninstall neuron to remove the virtual environment version of neuron. Then, try python -c "import neuron" to see if python can access your system-wide Neuron install.

[asoplata]

To be clearer, you can test that Neuron has been installed correctly before you install HNN:

1. In your virtual environment, run pip uninstall neuron like I said before, and follow the prompt.
2. Install NEURON using the Windows binaries from here, if you have not already done so: https://nrn.readthedocs.io/en/latest/install/install_instructions.html#windows
3. Next, open a new Terminal/Command Prompt for your virtual environment (close any old ones) and run python -c "import neuron". You can do this in a brand-new virtual environment if you want; ideally, all your Anaconda virtual environments should be able to import Neuron.
4. Now you should be able to install HNN.

If there are still issues, I strongly recommend first creating a new virtual environment using Anaconda, then testing that python -c "import neuron" works without installing anything else, then attempting to install HNN.

[dikshant182004]

i am very grateful for your time and guidance ,i have setup the system successfully # accomplished