DOC: Write sphinx extension to make nbsphinx work

Solves dynamicslab#230, replacing sphinx_nbexamples with nbsphinx

nbsphinx only works with notebooks in docs/, so copy examples/ to
docs/examples when building docs.  We lose the gallery, however.

Edit examples/README.rst to allow links to work from github to github,
but when docs built, links go from docs to docs.

docs/conf.py

@@ -1,5 +1,6 @@
 import importlib
-import pathlib
+import shutil
+from pathlib import Path
 
 author = "dynamicslab"
 project = "pysindy"  # package name
@@ -15,16 +16,17 @@
 master_doc = "index"
 
 extensions = [
+    "nbsphinx",
     "sphinxcontrib.apidoc",
     "sphinx.ext.autodoc",
     "sphinx.ext.todo",
     "sphinx.ext.viewcode",
     "sphinx.ext.autosummary",
     "sphinx.ext.napoleon",
     "sphinx.ext.mathjax",
-    "sphinx_nbexamples",
     "sphinx.ext.intersphinx",
 ]
+nb_execution_mode = "off"
 
 apidoc_module_dir = f"../{project}"
 apidoc_excluded_paths = ["tests"]
@@ -36,16 +38,11 @@
 
 language = "en"
 
-here = pathlib.Path(__file__).parent
+here = Path(__file__).parent.resolve()
 
 if (here / "static/custom.css").exists():
-
     html_static_path = ["static"]
 
-    def setup(app):
-        app.add_css_file("custom.css")
-
-
 exclude_patterns = ["build", "_build"]
 # pygments_style = "sphinx"
 
@@ -61,13 +58,6 @@ def setup(app):
 default_role = "any"
 html_sourcelink_suffix = ""
 
-example_gallery_config = dict(
-    dont_preprocess=True,
-    examples_dirs=["../examples"],
-    gallery_dirs=["examples"],
-    pattern=".+.ipynb",
-)
-
 intersphinx_mapping = {
     "derivative": ("https://derivative.readthedocs.io/en/latest/", None)
 }
@@ -110,3 +100,30 @@ def patched_parse(self):
 
 GoogleDocstring._unpatched_parse = GoogleDocstring._parse
 GoogleDocstring._parse = patched_parse
+
+
+def setup(app):
+    """Our sphinx extension for copying from examples/ to docs/examples
+
+    Since nbsphinx does not handle glob/regex paths, we need to
+    manually copy documentation source files from examples.  See issue
+    # 230.
+    """
+    doc_examples = here / "examples"
+    if not doc_examples.exists():
+        (here / "examples").mkdir()
+    example_source = (here / "../examples").resolve()
+    source_notebooks = example_source.glob("**/*.ipynb")
+    shutil.copy(example_source / "README.rst", doc_examples / "index.rst")
+    for notebook in source_notebooks:
+        if notebook.parent == example_source:
+            new_dir = doc_examples / notebook.stem
+        else:
+            new_dir = doc_examples / notebook.parent.stem
+        new_dir.mkdir(exist_ok=True)
+        new_file = new_dir / "example.ipynb"
+        print(f"Creating file {new_file}")
+        shutil.copy(notebook, new_file)
+
+    if (here / "static/custom.css").exists():
+        app.add_css_file("custom.css")

examples/README.rst

@@ -7,7 +7,7 @@ This directory showcases the following examples of PySINDy in action.
 -----------------------------------------------------------------------------------------------------------
 This notebook gives an almost exhaustive overview of the different features available in PySINDy. It's a good reference for how to set various options and work with different types of datasets.
 
-`Introduction to SINDy <https://pysindy.readthedocs.io/en/latest/examples/2_introduction_to_sindy.html>`_
+`Introduction to SINDy <./2_introduction_to_sindy/example.ipynb>`_
 ---------------------------------------------------------------------------------------------------------------------
 We recommend that people new to SINDy start here. We give a gentle introduction to the SINDy method and how different steps in the algorithm are represented in PySINDy. We also show how to use PySINDy to learn a model for a simple linear differential equation.
 
@@ -30,7 +30,7 @@ Shows how PySINDy interfaces with various Scikit-learn objects.
 * Cross-validation
 * Sparse regressors
 
-`Differentiation <https://pysindy.readthedocs.io/en/latest/examples/5_differentation.html>`_
+`Differentiation <./5_differentation/example.ipynb>`_
 ---------------------------------------------------------------------------------------------------------
 Explore the differentiation methods available in PySINDy on pure differentiation problems and as components in the SINDy algorithm.
 
@@ -44,7 +44,7 @@ Use the ``ConstrainedSR3`` optimizer to build a constrained model for the tempor
 
 
 `Trapping SINDy <https://pysindy.readthedocs.io/en/latest/examples/8_trapping_sindy_paper_examples.html>`_
-----------------------------------------------------------------------------------------------
+-----------------------------------------------------------------------------------------------------------
 This notebook applies the ``TrappingSR3`` optimizer to various canonical fluid systems., proposed in this paper: Kaptanoglu, Alan A., et al. "Promoting global stability in data-driven models of quadratic nonlinear dynamics." Physical Review Fluids 6.9 (2021): 094401. A preprint is found here `<https://arxiv.org/abs/2105.01843>`_.
 
 `SINDyPI <https://pysindy.readthedocs.io/en/latest/examples/9_sindypi_with_sympy.html>`_
@@ -56,11 +56,11 @@ This notebook applies the ``SINDyPI`` optimizer to a simple implicit ODE and was
 This notebook applies the PDEFIND algorithm (SINDy for PDE identification) to a number of PDEs, and was originally proposed in this paper: Rudy, Samuel H., et al. "Data-driven discovery of partial differential equations." Science Advances 3.4 (2017): e1602614.
 
 `Greedy Algorithms <https://pysindy.readthedocs.io/en/latest/examples/11_SSR_FROLS_examples.html>`_
-----------------------------------------------------------------------------------------------
+-----------------------------------------------------------------------------------------------------
 This notebook uses the step-wise sparse regression (SSR) and forward-regression orthogonal least-squares (FROLS) algorithms, which are greedy algorithms that iteratively truncate (or add) one nonzero coefficient at each algorithm iteration.
 
 `Weak formulation SINDy <https://pysindy.readthedocs.io/en/latest/examples/12_weakform_SINDy_examples.html>`_
-----------------------------------------------------------------------------------------------
+--------------------------------------------------------------------------------------------------------------
 This notebook uses SINDy to identify the weak-formulation of a system of ODEs or PDEs, adding significant robustness against noise in the data.
 
 `Model ensembles <https://pysindy.readthedocs.io/en/latest/examples/13_ensembling.html>`_
@@ -74,3 +74,8 @@ Demonstrates the use of SINDy to learn a model for the quasiperiodic dynamics in
 
 Full table of contents
 ----------------------
+.. toctree::
+    :glob:
+    :hidden:
+
+    **

requirements-dev.txt

@@ -16,7 +16,7 @@ sphinxcontrib-apidoc
 sphinx_rtd_theme
 pre-commit
 hypothesis
-sphinx-nbexamples
+nbsphinx
 jupyter_contrib_nbextensions
 pandas
 seaborn