On the number of segments needed in a piecewise linear approximation

The introduction of high-speed circuits to realize an arithmetic function f as a piecewise linear approximation has created a need to understand how the number of segments depends on the interval a≤x≤b and the desired approximation error ε. For the case of optimum non-uniform segments, we show that the number of segments is given as , (ε→0⁺), where . Experimental data shows that this approximation is close to the exact number of segments for a set of 14 benchmark functions. We also show that, if the segments have the same width (to reduce circuit complexity), then the number of segments is given by , (ε→0⁺), where .