FIX: slow `read_off` method #79

	name: pyncloud C.I.

	on:
	pull_request:
	branches:
	- master
	push:
	branches:
	- master

	jobs:
	build:

	strategy:
	max-parallel: 4
	matrix:
	python-version: [3.7, 3.8, 3.9]
	platform: [ubuntu-latest, macos-latest, windows-latest]
	runs-on: ${{ matrix.platform }}

	steps:
	- uses: actions/checkout@v1
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v1
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -r requirements.txt
	- name: Install pyntcloud
	run: \|
	pip install .
	- name: Lint with flake8
	run: \|
	pip install flake8
	# stop the build if there are Python syntax errors or undefined names
	flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
	# exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
	flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
	- name: Test and coverage with pytest
	run: \|
	pip install pytest
	pip install pytest-cov

	pytest --cov=pyntcloud --cov-report=xml --cov-append tests/unit
	pytest --cov=pyntcloud --cov-report=xml --cov-append tests/integration

	- name: Upload coverage to Codecov
	if: matrix.platform == 'ubuntu-latest' && matrix.python-version == '3.7'
	run: bash <(curl -s https://codecov.io/bash) -t $TOKEN -B $REF
	env:
	TOKEN: "${{ secrets.CODECOV_TOKEN }}"
	REF: "${{ github.ref }}"

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