fix 404 and intersphinx (#360)

* fix 404 and intersphinx

* Update examples/404.md

Co-authored-by: Thomas Wiecki <thomas.wiecki@gmail.com>

* default to stable now that 4.0 is released

Co-authored-by: Thomas Wiecki <thomas.wiecki@gmail.com>

Author: OriolAbril

examples/404.md

@@ -6,39 +6,9 @@ orphan: true
 
 **Sorry, we could not find this page**
 
-We are working on the next major release for PyMC,
-which will come with faster sampling, more flexible
-model building, multiple computational backends...
+Click on the navigation bar on top of the page to go to the right section
+of the default docs, or alternatively:
 
-::::{grid} 3
-:::{grid-item}
-![old banner](https://raw.githubusercontent.com/pymc-devs/pymc/v3/docs/logos/svg/PyMC3_banner.svg)
-:::
-:::{grid-item}
-:class: text-center
-{fas}`arrow-alt-circle-right;fa-5x`
-:::
-:::{grid-item}
-![new banner](https://raw.githubusercontent.com/pymc-devs/pymc/main/docs/logos/svg/PyMC_banner.svg)
-:::
-::::
-
-...and much better documentation too! However, to
-do so we have moved some files around and we have
-modified the base url in order to support multi version docs
-and better rendering and cross-referencing for notebooks.
-
-::::{grid} 3
-:::{grid-item}
-:::
-:::{grid-item}
-```{button-link} https://docs.pymc.io/projects/examples/en/latest/
-:color: primary
-:expand:
-
-Back to example gallery homepage
-```
-:::
-:::{grid-item}
-:::
-::::
+* Go to the current [PyMC example gallery homepage](https://www.pymc.io/projects/examples/en/latest/)
+* Go to the PyMC3 3.x snapshot of the [PyMC example gallery](https://www.pymc.io/projects/examples/en/2022.01.0/)
+  (also available for each page from the version switcher at the bottom right of the page)

examples/conf.py

@@ -189,6 +189,8 @@ def setup(app: Sphinx):
 # post_auto_image = 1
 # post_auto_excerpt = 2
 
+notfound_urls_prefix = "/projects/examples/en/latest/"
+
 # MyST config
 myst_enable_extensions = ["colon_fence", "deflist", "dollarmath", "amsmath", "substitution"]
 citation_code = f"""
@@ -251,7 +253,8 @@ def setup(app: Sphinx):
     "mpl": ("https://matplotlib.org/", None),
     "numpy": ("https://numpy.org/doc/stable/", None),
     "pandas": ("https://pandas.pydata.org/pandas-docs/stable/", None),
-    "pymc": ("https://docs.pymc.io/en/latest/", None),
+    "pymc": ("https://www.pymc.io/projects/docs/en/stable/", None),
+    "pmx": ("https://www.pymc.io/projects/experimental/en/latest/", None),
     "scipy": ("https://docs.scipy.org/doc/scipy/reference/", None),
     "xarray": ("http://docs.xarray.dev/en/stable/", None),
 }

examples/index.md

@@ -5,8 +5,8 @@
 
 Home <https://www.pymc.io>
 Examples <gallery>
-Learn <https://www.pymc.io/projects/docs/en/latest/learn.html>
-API <https://www.pymc.io/projects/docs/en/latest/api.html>
+Learn <https://www.pymc.io/projects/docs/en/stable/learn.html>
+API <https://www.pymc.io/projects/docs/en/stable/api.html>
 Community <https://www.pymc.io/community/index.html>
 Contributing <https://www.pymc.io/projects/docs/en/latest/contributing/index.html>
 :::