API Reference > geometry-core > Curve > CurveChainWithDistanceIndex > fractionToPointAnd2Derivatives fractionToPointAnd2Derivatives Method Return a plane with origin at fractional position along the curve vectorU is the first derivative, i.e. tangent vector with length equal to the rate of change with respect to the fraction. vectorV is the second derivative, i.e.derivative of vectorU. fractionToPointAnd2Derivatives(fraction: number, result?: Plane3dByOriginAndVectors): undefined | Plane3dByOriginAndVectors Parameter Type Description fraction number result Plane3dByOriginAndVectors Returns - undefined | Plane3dByOriginAndVectors Defined in curve/CurveChainWithDistanceIndex.ts Line 450 Last Updated: 12 June, 2024