Fixed in Origin 2018. Bug in Origin 2017. For example:
angleint2(1,1,3,3,5,7,6,9,0) =; --> returns 0.32175055439664, which is radian result
angleint2(1,1,3,3,5,7,6,9,1) =; ==> still returns 0.32175055439664, but it should return degree result 18.434948822922