Add tetrahedral grid #127

	# GitHub action workflow that performs a source code formatting check.
	#
	# The workflow fails if one or more of the .hpp or .cpp files in the repository
	# are not properly formatted according to the rules in the .clang-format file
	# located in the root of the repository directory, using clang-format version 18.
	# In that case, the log file provides a list of improperly formatted files.
	# Source files with other extensions (including .h, .c, .hh, .cc) are NOT tested
	# to allow for differently formatted third-party code.
	#
	name: Check formatting

	# workflow event triggers
	on: pull_request

	# jobs that run
	jobs:
	# automatic formatting check
	check_formatting_job:
	# job name, displayed in the action log
	name: Check source code formatting
	# run this job on a Github-provided runner with Ubuntu 24.04
	# because it has clang-format-18 installed
	runs-on: ubuntu-24.04
	# steps that make up this job
	steps:
	# checkout using a recent version of the checkout action
	- name: Checkout
	uses: actions/checkout@v3
	# run clang-format on all .hpp and .cpp files, writing any errors to a text file
	- name: Autoformat
	run: \|
	find . \( -name '.hpp' -or -name '.cpp' \) -exec clang-format-18 -style=file -i {} 2> formaterror.txt \;
	cat formaterror.txt
	bash -c "if [ -s formaterror.txt ] ; then exit 1 ; fi"
	# fail the workflow if anything changed to the repository
	- name: Verify
	run: git diff --stat --no-ext-diff --exit-code

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