macOS get average time for 10 command runs, using coreutils/date and node

atime.sh

atime() {
	local times=()
	local start end total
	
	for i in {1..10}; do
		start=$(/usr/local/opt/coreutils/libexec/gnubin/date +%s%N)
		"$@" >/dev/null 2>&1
		end=$(/usr/local/opt/coreutils/libexec/gnubin/date +%s%N)
		total=$(expr $end - $start)
		times+=( $total )
		node -p "Math.round(($total)/1000)/1000000"
	done

	times=$(echo ${times[@]} | tr " " ",")

	node -e " \
a=[${times}]; \
r=i=>Math.round(i/1000)/1000000; \
a.sort((a,b)=>a-b); \
avg=a.reduce((a,b)=>a+b)/a.length; \
precision=Math.round((avg-a[0])/avg*100); \
console.log('------------');
console.log(r(avg) + ' ±' + precision + '%'); \
"
}