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

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

# # Specifying Thumbnails in `conf.py`
# 
# This notebook doesn't contain any thumbnail metadata.
# 
# But in the file [conf.py](../conf.py),
# a thumbnail is specified (via the
# [nbsphinx_thumbnails](../usage.ipynb#nbsphinx_thumbnails)
# option),
# which will be used in the [gallery](../subdir/gallery.ipynb).
# 
# The keys in the `nbsphinx_thumbnails` dictionary can contain wildcards,
# which behave very similarly to the
# [html_sidebars](https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_sidebars)
# option.
# 
# The thumbnail files can be local image files somewhere in the source directory,
# but you'll need to create at least one
# [link](../markdown-cells.ipynb#Links-to-Local-Files)
# to them in order to copy them to the HTML output directory.
# 
# You can also use files from the `_static` directory
# (which contains all files in your [html_static_path](https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_static_path)).
# 
# If you want, you can also use files from the `_images` directory,
# which contains all notebook outputs.

# To demonstrate this feature,
# we are creating an image file here:

# In[ ]:


get_ipython().run_line_magic('matplotlib', 'agg')


# In[ ]:


import matplotlib.pyplot as plt


# In[ ]:


fig, ax = plt.subplots()
ax.plot([4, 8, 15, 16, 23, 42])
fig.savefig('a-local-file.png')


# Please note that the previous cell doesn't have any outputs,
# but it has generated a file named `a-local-file.png` in the notebook's directory.
# 
# We have to create a link to this file (which is a good idea anyway):
# [a-local-file.png](a-local-file.png).
# 
# Now we can use this file in our [conf.py](../conf.py) like this:
# 
# ```python
# nbsphinx_thumbnails = {
#     'gallery/thumbnail-from-conf-py': 'gallery/a-local-file.png',
# }
# ```
# 
# Please note that the notebook name does *not* contain the `.ipynb` suffix.