Abstract: A method for approximating a mathematical function defined over a range includes initially dividing at least part of the range into a set of segments. For at least a subset of the segments, the mathematical function is approximated within each segment by a respective approximation polynomial. A series of one or more segment-merging iterations is performed, a given iteration including: selecting adjacent segments as candidates for merging; approximating the mathematical function by a candidate approximation polynomial, over at least a merged segment formed by merging the adjacent segments; and, if approximation of the mathematical function meets a specified condition, updating the set of segments by (i) replacing the adjacent segments with the merged segment and (ii) replacing the approximation polynomials of the adjacent segments with the candidate approximation polynomial.