#!/usr/bin/env python
# coding: utf-8

# This notebook is part of the `nbsphinx` documentation: https://nbsphinx.readthedocs.io/.

# # Configuring the Kernels

# ## Kernel Name
# 
# If we have multiple kernels installed, we can choose to override the kernel saved in the notebook using [nbsphinx_kernel_name](configuration.ipynb#nbsphinx_kernel_name):
# ```python
# nbsphinx_kernel_name = 'python-upstream-dev'
# ```
# which uses the kernel named `python-upstream-dev` instead of the kernel name stored in the notebook.

# ## Kernel Arguments
# 
# We can pass arguments to the kernel by using
# [nbsphinx_execute_arguments](configuration.ipynb#nbsphinx_execute_arguments),
# for example to set [plot options](code-cells.ipynb#Plots):
# 
# ```python
# nbsphinx_execute_arguments = [
#     "--InlineBackend.figure_formats={'svg', 'pdf'}",
# ]
# ```

# ## Environment Variables
# 
# The contents of `os.environ` after the execution of `conf.py` will be passed as environment variables to the kernel. As an example, `MY_DUMMY_VARIABLE` has been set in [conf.py](conf.py) like this:
# 
# ```python
# import os
# os.environ['MY_DUMMY_VARIABLE'] = 'Hello from conf.py!'
# ```
# 
# ... and it can be checked in the notebook like this:

# In[ ]:


import os
os.environ['MY_DUMMY_VARIABLE']


# This is useful if we want to edit `PYTHONPATH` in order to compile the documentation without installing the project:
# ```python
# import os
# 
# src = os.path.abspath('../src')
# os.environ['PYTHONPATH'] = src
# ```

# If you are using https://mybinder.org/ and you want to define environment variables,
# you should create a file `.binder/start` in your repository
# (see [Binder docs](https://mybinder.readthedocs.io/en/latest/using/config_files.html#start-run-code-before-the-user-sessions-starts))
# containing definitions like this:
# 
# ```bash
# #!/bin/bash
# export MY_DUMMY_VARIABLE="Hello from .binder/start!"
# exec "$@"
# ```