Add comprehensive documentation with Sphinx and GitHub Pages deployment

.github/workflows/docs.yml

@@ -0,0 +1,67 @@
+name: Build and Deploy Documentation
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: "pages"
+  cancel-in-progress: false
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+
+      - name: Install dependencies
+        run: |
+          sudo apt-get update -qq
+          sudo apt-get install -y -qq pandoc
+          python -m pip install --upgrade pip
+          pip install numpy==2.3.5 numba==0.63.1
+          pip install sphinx>=7.0.0 sphinx-rtd-theme>=2.0.0 nbsphinx>=0.9.0 ipython>=8.0.0
+
+      - name: Build documentation
+        run: |
+          cd docs
+          make html
+          touch build/html/.nojekyll
+
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: 'docs/build/html'
+
+  deploy:
+    # Only deploy on push to main branch
+    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+
+    runs-on: ubuntu-latest
+    needs: build
+
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4

.gitignore

@@ -26,6 +26,13 @@ venv/
 ENV/
 env/
 
+# Documentation builds
+docs/build/
+docs/source/_build/
+
+# Jupyter Notebook checkpoints
+.ipynb_checkpoints
+
 # IDE
 .vscode/
 .idea/

docs/Makefile

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+# Minimal makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line, and also
+# from the environment for the first two.
+SPHINXOPTS    ?=
+SPHINXBUILD   ?= sphinx-build
+SOURCEDIR     = source
+BUILDDIR      = build
+
+# Put it first so that "make" without argument is like "make help".
+help:
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+
+.PHONY: help Makefile
+
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)

docs/README.md

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+# Documentation Build Guide
+
+This guide explains how to build the CudAkima documentation locally.
+
+## Prerequisites
+
+You need to install the documentation dependencies:
+
+```bash
+# Using pip
+pip install -e ".[docs]"
+
+# Or install dependencies individually
+pip install sphinx>=7.0.0 sphinx-rtd-theme>=2.0.0 nbsphinx>=0.9.0 ipython>=8.0.0
+```
+
+## Building the Documentation
+
+To build the HTML documentation:
+
+```bash
+cd docs
+make html
+```
+
+The generated documentation will be in `docs/build/html/`. Open `docs/build/html/index.html` in your browser to view it.
+
+## Cleaning Build Files
+
+To clean the build directory:
+
+```bash
+cd docs
+make clean
+```
+
+## Other Output Formats
+
+Sphinx supports multiple output formats. Some useful ones:
+
+```bash
+# PDF (requires LaTeX)
+make latexpdf
+
+# Plain text
+make text
+
+# ePub
+make epub
+```
+
+## GitHub Pages Deployment
+
+The documentation is automatically built and deployed to GitHub Pages when changes are pushed to the `main` branch. The workflow is defined in `.github/workflows/docs.yml`.
+
+To enable GitHub Pages:
+
+1. Go to your repository settings on GitHub
+2. Navigate to "Pages" in the left sidebar
+3. Under "Source", select "GitHub Actions"
+4. The documentation will be available at `https://<username>.github.io/<repository>/`
+
+## Documentation Structure
+
+```
+docs/
+├── source/
+│   ├── conf.py           # Sphinx configuration
+│   ├── index.rst         # Main documentation page
+│   ├── api.rst           # API reference
+│   ├── tutorial.rst      # Tutorial page
+│   ├── examples.rst      # Examples page
+│   ├── notebooks/        # Jupyter notebooks
+│   │   └── tutorial.ipynb (symlink to examples/tutorial.ipynb)
+│   ├── _static/          # Static files (CSS, images, etc.)
+│   └── _templates/       # Custom templates
+├── build/                # Generated documentation (git-ignored)
+└── Makefile             # Build commands
+```
+
+## Updating Documentation
+
+1. **Class/Function Documentation**: Update docstrings in the source code (`src/cudakima/`)
+2. **Tutorial**: Edit `examples/tutorial.ipynb`
+3. **Examples**: Edit `docs/source/examples.rst`
+4. **Main Pages**: Edit `.rst` files in `docs/source/`
+
+After making changes, rebuild the documentation to see the updates:
+
+```bash
+cd docs
+make clean
+make html
+```
+
+## Docstring Format
+
+CudAkima uses NumPy-style docstrings. Here's an example:
+
+```python
+def my_function(x, y):
+    """
+    Short description.
+
+    Longer description if needed.
+
+    Parameters
+    ----------
+    x : array_like
+        Description of x
+    y : float
+        Description of y
+
+    Returns
+    -------
+    result : ndarray
+        Description of return value
+
+    Examples
+    --------
+    >>> my_function([1, 2, 3], 2.0)
+    array([2., 4., 6.])
+    """
+    pass
+```
+
+## Troubleshooting
+
+### Import Errors
+
+If you get import errors when building the documentation, make sure the package is installed:
+
+```bash
+pip install -e .
+```
+
+### Notebook Execution Errors
+
+The notebooks are set to not execute during the build (`nbsphinx_execute = 'never'`). If you want to execute them, change this setting in `docs/source/conf.py`.
+
+### Missing Dependencies
+
+If you get warnings about missing dependencies, install them:
+
+```bash
+pip install -e ".[docs]"
+```

docs/source/api.rst

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+API Reference
+=============
+
+This page documents the complete API for CudAkima.
+
+Main Classes
+------------
+
+.. currentmodule:: cudakima
+
+AkimaInterpolant1D
+~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: cudakima.AkimaInterpolant1D
+   :members:
+   :special-members: __init__, __call__
+   :show-inheritance:
+
+AkimaInterpolant1DMultiDim
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: cudakima.AkimaInterpolant1DMultiDim
+   :members:
+   :special-members: __init__, __call__
+   :show-inheritance:
+
+AkimaInterpolant1DFlexible
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: cudakima.AkimaInterpolant1DFlexible
+   :members:
+   :special-members: __init__, __call__
+   :show-inheritance:
+
+Kernel Functions
+----------------
+
+This section documents the low-level numba kernels used for GPU and CPU computation.
+
+GPU Kernels
+~~~~~~~~~~~
+
+.. currentmodule:: cudakima.kernels
+
+.. autofunction:: linearslope_gpu
+
+.. autofunction:: splineslope_gpu
+
+.. autofunction:: splineslope_gpu_optimized
+
+.. autofunction:: binary_search_gpu
+
+.. autofunction:: akima_spline_kernel_gpu
+
+.. autofunction:: akima_spline_kernel_optimized
+
+.. autofunction:: akima_linear_kernel
+
+.. autofunction:: precompute_slopes_kernel
+
+.. autofunction:: precompute_spline_slopes_kernel
+
+.. autofunction:: akima_linear_kernel_gpu_multidim
+
+.. autofunction:: akima_spline_kernel_gpu_multidim
+
+CPU Kernels
+~~~~~~~~~~~
+
+.. autofunction:: linearslope_cpu
+
+.. autofunction:: splineslope_cpu
+
+.. autofunction:: splineslope_cpu_optimized
+
+.. autofunction:: binary_search_cpu
+
+.. autofunction:: akima_spline_kernel_cpu
+
+.. autofunction:: akima_spline_kernel_cpu_optimized
+
+.. autofunction:: akima_linear_kernel_cpu
+
+.. autofunction:: precompute_all_linear_slopes_cpu
+
+.. autofunction:: precompute_all_spline_slopes_cpu
+
+.. autofunction:: akima_linear_kernel_cpu_multidim
+
+.. autofunction:: akima_spline_kernel_cpu_multidim