Add chi square calculation function to math module. #173

	name: Check branch status

	on:
	pull_request:
	branches:
	- "**"

	jobs:
	check_branch_history:
	name: Check - Linear history
	runs-on: ubuntu-latest
	steps:
	- name: Checkout source code
	uses: actions/checkout@v3
	with:
	ref: ${{ github.event.pull_request.head.sha }} # otherwise, it'd create a merge commit
	fetch-depth: "0"
	- name: Check HEAD is rebased on ${{ github.event.pull_request.base.ref }}
	run: \|
	git config --global user.name "$GITHUB_ACTOR"
	git config --global user.email "[email protected]"
	git fetch origin $GITHUB_BASE_REF
	PR_HEAD_SHA=$(git rev-parse HEAD)
	git rebase FETCH_HEAD
	REBASED_SHA=$(git rev-parse HEAD)
	echo "PR HEAD: $PR_HEAD_SHA"
	echo "Rebased HEAD: $REBASED_SHA"
	git range-diff FETCH_HEAD..$PR_HEAD_SHA FETCH_HEAD..$REBASED_SHA
	if [[ "$REBASED_SHA" != "$PR_HEAD_SHA" ]]; then
	echo "Not fast forward, aborting!"
	echo "Ensure that the PR branch is rebased on $GITHUB_BASE_REF and does not contain merge commits."
	exit 1
	fi

Provide feedback