Added pop_matrix, update_matrix and as_int for matrix operations #73

	# This workflow will install Python dependencies, run tests and lint with a variety of Python versions

	name: PegasusIO CI

	on:
	pull_request:
	branches:
	- master

	jobs:
	build:

	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ubuntu-latest]
	python-version: ['3.7', '3.8', '3.9']

	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	python -m pip install flake8 pytest setuptools wheel
	python -m pip install -e .
	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	flake8 . --count --select=E9,F63,F7 --show-source --statistics
	- name: Fetch test data
	run: \|
	sudo apt -q update
	sudo apt install -y git
	git clone https://github.com/lilab-bcb/pegasusio-test-data.git ./pegasusio-test-data
	- name: IO test
	run: \|
	pytest tests/test_io.py
	- name: Data aggregation test
	run: \|
	bash tests/run_aggregate_matrix.sh
	pytest tests/test_aggr.py

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