API Reference > geometry-core > CartesianGeometry > Ellipsoid > radiansToFrenetFrame radiansToFrenetFrame Method Evaluate a point and rigid local coordinate frame the ellipsoid at angles give in radians. The undefined return is only possible if the placement transform is singular (and even then only at critical angles) radiansToFrenetFrame(thetaRadians: number, phiRadians: number, result?: Transform): undefined | Transform Parameter Type Description thetaRadians number longitude, in radians phiRadians number latitude, in radians result Transform optional transform result Returns - undefined | Transform Defined in geometry3d/Ellipsoid.ts Line 616 Last Updated: 11 June, 2024