3ds Max Animation :: Snapping IK To FK Script

I created this script to snap a three-bone IK chain to a three-bone FK chain. It works by first creating a line between the first and last bones in the IK chain, then it positions two point helpers (call them pointA and pointB) on the pivots of the second bone in the IK and FK chain.

Using the nearestPathParam function we can find a value (between 0 and 1) such that pointA and pointB lie on the normal plane to the straight line and then use the pathInterp function to translate the parameter into a position vector which we can use to position another helper (call it pointC) to then calculate the angle between (pointA - pointC) and (pointB - pointC). Sometimes the angle is calculated incorrectly, which is why I put an if-statement in towards the end to deal with this case; simply put a negative sign infront of the swivel angle.

(
local arrayIK = #($Bone_IK01, $Bone_IK02, $Bone_IK03),
arrayFK = #($Bone_FK01, $Bone_FK02, $Bone_FK03),
IKGoal = $'IK Chain001'
function snapIKFK IKarray FKarray =
(
IKGoal.transform.controller.swivelAngle = 0
[code].....

I'm not a good scripter, so the script looks a little clunky. I'm also having the problem that the script doesn't work when I try to activate it through a button press, it says "--Type error: Call needs function or class, got:

ButtonControl:snapIKFK".