  The $\epsilon$-subdifferential of convex univariate piecewise
linear-quadratic functions can be computed in linear worst-case time complexity
as the level-set of a convex function. Using dichotomic search, we show how the
computation can be performed in logarithmic worst-case time. Furthermore, a new
algorithm to compute the entire graph of the $\epsilon$-subdifferential in
linear time is presented. Both algorithms are not limited to convex PLQ
functions but are also applicable to any convex piecewise-defined function with
little restrictions.
