add: symmetric value function #198

	name: Build Documentation

	on:
	push:
	pull_request:

	jobs:
	build_docs:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.10"]
	fail-fast: false

	defaults:
	run:
	shell: bash -l {0}

	steps:
	- name: Set env vars
	run: \|
	export REPOSITORY_NAME=${GITHUB_REPOSITORY#*/} # just the repo, as opposed to org/repo
	echo "REPOSITORY_NAME=${REPOSITORY_NAME}" >> $GITHUB_ENV

	- name: Checkout the code
	uses: actions/checkout@v3
	with:
	fetch-depth: 1000 # should be enough to reach the most recent tag

	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}

	- name: Install documentation-building requirements
	run: \|
	# For reference: https://www.gnu.org/software/bash/manual/html_node/The-Set-Builtin.html.
	set -vxeuo pipefail

	# These packages are installed in the base environment but may be older
	# versions. Explicitly upgrade them because they often create
	# installation problems if out of date.
	python -m pip install --upgrade pip setuptools numpy

	pip install .
	pip install -r requirements-dev.txt
	pip list

	- name: Build Docs
	run: make -C docs/ html

	- uses: actions/upload-artifact@v3
	with:
	name: ${{ env.REPOSITORY_NAME }}-docs
	path: docs/build/html/

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