xxii P REFACE TO THE S ECOND E DITION
algorithms (Chapter 15) and the discussion of primal barrier methods moved to the new
interior-point chapter. There is much new material in this part, including a treatment of
nonlinear programming duality, an expanded discussion of algorithms for inequality con-
strained quadratic programming, a discussion of dual simplex and presolving in linear
programming, a summary of practical issues in the implementation of interior-point linear
programming algorithms, a description of conjugate-gradient methods for quadratic pro-
gramming, and a discussion of filter methods and nonsmooth penalty methods in nonlinear
programming algorithms.
In many chapters we have added a Perspectives and Software section near the end, to
place the preceding discussion in context and discuss the state of the art in software. The
appendix has been rearranged with some additional topics added, so that it can be used
in a more stand-alone fashion to cover some of the mathematical background required
for the rest of the book. The exercises have been revised in most chapters. After these
many additions, deletions, and changes, the second edition is only slightly longer than the
first, reflecting our belief that careful selection of the material to include and exclude is an
important responsibility for authors of books of this type.
A manual containing solutions for selected problems will be available to bona fide
instructors through the publisher. A list of typos will be maintained on the book’s web site,
which is accessible from the web pages of both authors.
We acknowledge with gratitude the comments and suggestions of many readers of the
first edition, who sent corrections to many errors and provided valuable perspectives on the
material, which led often to substantial changes. We mention in particular Frank Curtis,
Michael Ferris, Andreas Griewank, Jacek Gondzio, Sven Leyffer, Philip Loewen, Rembert
Reemtsen, and David Stewart.
Our special thanks goes to Michael Overton, who taught from a draft of the second
edition and sent many detailed and excellent suggestions. We also thank colleagues who
read various chapters of the new edition carefully during development, including Richard
Byrd, Nick Gould, Paul Hovland, Gabo Lop
´
ez-Calva, Long Hei, Katya Scheinberg, Andreas
W
¨
achter, and Richard Waltz. We thank Jill Wright for improving some of the figures and for
the new cover graphic.
We mentioned in the original preface several areas of optimization that are not
covered in this book. During the past six years, this list has only grown longer, as the field
has continued to expand in new directions. In this regard, the following areas are particularly
noteworthy: optimization problems with complementarity constraints, second-order cone
and semidefinite programming, simulation-based optimization, robust optimization, and
mixed-integer nonlinear programming. All these areas have seen theoretical and algorithmic
advances in recent years, and in many cases developments are being driven by new classes
of applications. Although this book does not cover any of these areas directly, it provides a
foundation from which they can be studied.
Jorge Nocedal Stephen J. Wright
Evanston, IL Madison, WI