Activity › Forums › Adobe After Effects Expressions › error: Math.trunc() is not a function Adobe After Effects Expressions error: Math.trunc() is not a function Posted by Seth Olson on December 19, 2022 at 5:48 pm it suggests Math.trunc() when i type it, but then it says its not a function. The slider is a number, and did parseInt() to make sure it was a number. I’m in AE 23.1.0 Seth Olson replied 3 years, 4 months ago 2 Members · 2 Replies 2 Replies Dan Ebberts December 19, 2022 at 6:20 pm You probably have File > Project Settings > Expressions set to Legacy ExtendScript. Change it to JavaScript and the error should go away. Seth Olson December 19, 2022 at 6:21 pm oh wow, thank you! Not sure how that happened. Reply to this Discussion! Login or Sign Up Public All Members My Connections Only Me PublicAll MembersMy ConnectionsOnly Me Public All Members My Connections Only Me Reply to this Discussion! Login or Sign Up