gh-35: Sphinx documentation

.readthedocs.yml

@@ -0,0 +1,13 @@
+version: 2
+
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.12"
+
+python:
+  install:
+    - method: pip
+      path: .
+      extra_requirements:
+        - docs

README.md

@@ -6,6 +6,8 @@ healpix
 This package implements a lean set of routines for working with the HEALPix
 discretisation of the sphere.  It supports NSIDE parameters up to 2^29.
 
+The online documentation can be found [here](http://healpix.readthedocs.io).
+
 The C library is based on the *healpix_bare* library, which was released under
 the 3-clause BSD license, with the following additions:
 
@@ -38,9 +40,6 @@ The Python package consists of two modules:
 
   * Random point picking in HEALPix pixels.
 
-For a function reference, run `pydoc healpix` (or `pydoc chealpix`) locally if
-you have the package installed, or see the [online reference][pydoc].
-
 The high-level functions in the `healpix` module can be used more or less
 interchangeably with functions from the *healpy* package.  However, in some
 cases, compatibility is sacrificed for consistency.
@@ -67,5 +66,3 @@ and therefore have minimal memory overhead:
 >>> 
 >>> # no memory overhead: only the 2G output arrays were used
 ```
-
-[pydoc]: https://github.com/ntessore/healpix/raw/main/python/reference.txt

docs/.gitignore

@@ -0,0 +1 @@
+_build

docs/Makefile

@@ -0,0 +1,20 @@
+# 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     = .
+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/chealpix.rst

@@ -0,0 +1,15 @@
+
+:mod:`chealpix` -- Python bindings
+==================================
+
+.. currentmodule:: chealpix
+.. module:: chealpix
+
+Vectorised Python bindings to the HEALPix C library.
+
+.. data:: NSIDE_MAX
+
+   Maximum admissible value for the NSIDE parameter.
+
+   If nside > NSIDE_MAX is used, the resulting pixel indices can overflow their
+   underlying integer type in the C library functions.

docs/conf.py

@@ -0,0 +1,33 @@
+# Configuration file for the Sphinx documentation builder.
+#
+# For the full list of built-in configuration values, see the documentation:
+# https://www.sphinx-doc.org/en/master/usage/configuration.html
+
+# -- Project information -----------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
+
+from importlib import metadata
+
+project = 'healpix'
+copyright = '2024, Nicolas Tessore'
+author = 'Nicolas Tessore'
+version = metadata.version(project)
+release = version
+
+# -- General configuration ---------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
+
+extensions = [
+    'sphinx.ext.autodoc',
+]
+
+templates_path = ['_templates']
+exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
+
+
+
+# -- Options for HTML output -------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
+
+html_theme = 'furo'
+html_static_path = ['_static']

docs/healpix.rst

@@ -0,0 +1,62 @@
+
+:mod:`healpix` -- Python module
+===============================
+
+.. currentmodule:: healpix
+.. module:: healpix
+
+Python module for the HEALPix discretisation of the sphere.
+
+
+Resolution
+----------
+
+.. autodata:: NSIDE_MAX
+
+.. function:: nside2npix(nside)
+              npix2nside(npix)
+
+   Convert between resolution parameter *nside* and number of pixels *npix*.
+
+
+.. function:: nside2order(nside)
+              order2nside(order)
+
+   Convert between resolution parameter *nside* and HEALPix order *order*.
+   Requires *nside* to be a power of two.
+
+
+Pixel routines
+--------------
+
+.. function:: ang2pix(nside, theta, phi, nest=False, lonlat=False)
+              pix2ang(nside, ipix, nest=False, lonlat=False)
+
+.. function:: pix2vec(nside, ipix, nest=False)
+              vec2pix(nside, x, y, z, nest=False)
+
+.. function:: ang2vec(theta, phi, lonlat=False)
+              vec2ang(x, y, z, lonlat=False)
+
+.. function:: ring2nest(nside, ipix)
+              nest2ring(nside, ipix)
+
+
+Subpixel indexing
+-----------------
+
+
+Random point picking
+--------------------
+
+.. autofunction:: randang
+.. autofunction:: randvec
+
+
+Multi-Order Coverage (MOC)
+--------------------------
+
+.. function:: pix2uniq(order, ipix, nest=False)
+              uniq2pix(uniq, nest=False)
+
+   Convert pixel indices to or from the UNIQ pixel indexing scheme.

docs/index.rst

@@ -0,0 +1,19 @@
+
+Welcome to healpix's documentation!
+===================================
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Contents
+
+   healpix
+   chealpix
+   library
+
+
+Indices and tables
+==================
+
+* :ref:`genindex`
+* :ref:`modindex`
+* :ref:`search`

docs/library.rst

@@ -0,0 +1,15 @@
+C library
+=========
+
+The C library consists of a header ``healpix.h`` and source ``healpix.c``.  The
+files have no requirements besides a C99-compatible compiler, and are usually
+copied directly into a project.
+
+
+Reference
+---------
+
+The contents of the ``healpix.h`` header file are reproduced below.
+
+.. literalinclude:: ../src/healpix.h
+   :language: c

docs/make.bat

@@ -0,0 +1,35 @@
+@ECHO OFF
+
+pushd %~dp0
+
+REM Command file for Sphinx documentation
+
+if "%SPHINXBUILD%" == "" (
+	set SPHINXBUILD=sphinx-build
+)
+set SOURCEDIR=.
+set BUILDDIR=_build
+
+%SPHINXBUILD% >NUL 2>NUL
+if errorlevel 9009 (
+	echo.
+	echo.The 'sphinx-build' command was not found. Make sure you have Sphinx
+	echo.installed, then set the SPHINXBUILD environment variable to point
+	echo.to the full path of the 'sphinx-build' executable. Alternatively you
+	echo.may add the Sphinx directory to PATH.
+	echo.
+	echo.If you don't have Sphinx installed, grab it from
+	echo.https://www.sphinx-doc.org/
+	exit /b 1
+)
+
+if "%1" == "" goto help
+
+%SPHINXBUILD% -M %1 %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O%
+goto end
+
+:help
+%SPHINXBUILD% -M help %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O%
+
+:end
+popd