Embodiments of the present invention provide a method of determining whether data exceeds a validity range of an operation, comprising dividing operation data indicative of a range of validity of the operation into a plurality of chunks, determining a partial convex hull for each of the plurality of chunks, determining a convex hull for the operation data based on the plurality of partial convex hulls, and determining whether the data exceeds the validity range of the operation data based on the convex hull.