Fix: checkmatrix check for empty histogram #39

	name: Code Formatting

	on: [push, pull_request]

	jobs:
	python-formatting:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions/setup-python@v2
	with:
	python-version: '3.x'
	- name: Install black
	run: pip install black && black --version
	- name: Run black
	run: black --check .
	flake8-lint:
	runs-on: ubuntu-latest
	name: flake8 lint
	steps:
	- uses: actions/checkout@v2
	- uses: actions/setup-python@v2
	with:
	python-version: "3.x"
	- name: flake8 lint
	uses: py-actions/flake8@v2

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