Revised algorithm for islanding detection. #2039

	name: Python application

	on: [push, pull_request]

	jobs:
	build:

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v1
	- name: Set up Python 3.9
	uses: actions/setup-python@v1
	with:
	python-version: 3.9
	- name: Install dependencies
	run: \|
	# work around a pip issue with extras_require: https://github.com/pypa/pip/issues/8323
	python -m pip install -U "pip @ git+https://github.com/pypa/pip.git"
	python -m pip install --upgrade pip
	python -m pip install .[all]
	python -m pip install nbmake==0.10 pytest-xdist line_profiler # add'l packages for notebook tests.
	- name: Lint with flake8 for pull requests
	if: github.event_name == 'pull_request'
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	flake8 .
	- name: Test with pytest
	run: \|
	pytest --log-cli-level=10
	- name: Test notebooks.
	run: \|
	pytest --log-cli-level=10 --nbmake examples --ignore=examples/verification
	- name: Build a distribution if tagged
	if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags')
	run: \|
	python setup.py sdist
	- name: Publish a Python distribution to PyPI if tagged
	if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags')
	uses: pypa/gh-action-pypi-publish@master
	with:
	user: __token__
	password: ${{ secrets.pypi_password }}

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