[net.vlsi] package for solution of nonlinear constrained problems

jabarby@wateng.UUCP (Jim Barby) (08/05/83)

The new optimization package developed at U of W is now available
on Unix.  The following are excerpts from watopt's documentation.
Direct all inquires to jabarby@wateng or come and see me (my office
is cph3372g).
Jim Barby
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                    WATOPT USER'S GUIDE
                         R. Chadha
                         K. Singhal
                          J. Vlach
                   Faculty of Engineering
                            and
              Institute for Computer Research
                   University of Waterloo
                 Waterloo, Ontario, Canada
                          ABSTRACT
          This guide describes the use  of  the  WATOPT
     (Waterloo  Optimization)  package for the solution
     of nonlinear constrained  problems  in  which  the
     function  and  constraint gradients are available.
     WATOPT implements  the  Han-Powell  alogrithm  but
     uses  a  quadratic  program  that  is specifically
     tailored to this problem.  It  requires  60%  less
     storage  and  at  least an order of magnitude less
     computational  effort   as   compared   with   the
     corresponding Harwell routine VF02AD.
-------------------------
     WATOPT  [1]  has  been  implemented  on  the  IBM  4341
(VM/CMS)  under  the  IBM  FORTRAN/VS complier.  It has also
been implemented on VAX/VMS in FORTRAN 77  and  VAX/UNIX  in
f77.   The  program  has  783 lines of FORTRAN code and uses
double precision arithmetic for computations.   WATOPT  con-
sists  of 4 major routines (namely - WATOPA, WATOPB, WATOPC,
and WATOPD) and 6 peripheral routines. It also uses 11  rou-
tines from the LINPACK library.
     WATOPT utilizes the sequential programming approach for
general  nonlinear  constrained optimization [2], similar to
that employed in the Harwell library  program  VF02AD.   The
user specifies starting values of the variables and the pro-
gram modifies them till the solution is attained.  Provision
has  been  made  for  incorporating an arbitrary number of z
variables in the optimization procedure.   The  z  variables
are  such that there are no quadratic terms in the quadratic
function to be minimized at each iteration [1].  Examples of
these  variables are the artificial variables introduced for
minimax objectives and for ratio bounds.
     The number of iterations t  before  the  watchdog  pro-
cedure retraces back to the previous minimum has been chosen
to be 5 [1].  Also if the relaxed  criterion  fails  at  any
stage  then  subsequent  iterations employ only the standard
search.
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WATOPT(3F)          UNIX Programmer's Manual           WATOPT(3F)
NAME
     watopt - an optimization program written in Fortran
SYNOPSIS
     WATOPT [1]  consists of 4 major routines (namely - WATOPA,
     WATOPB, WATOPC, and WATOPD) and 6 peripheral routines and it
     uses 11 routines from the LINPACK library.  It utilizes the
     sequential quadratic programming approach for general non-
     linear constrained optimization [2], similar to that
     employed in the Harwell library program VF02AD.  However,
     WATOPT requires 60% less storage and is atleast one order of
     magnitude faster.  The user specifies starting values of the
     variables and the program modifies them till the solution is
     attained.
FILES
     /u/jabarby/lib/libwatopt.a
     /u/jabarby/lib/liblinpack.a
     /u/jabarby/libraries/numerical/doc/watopt
     /u/jabarby/libraries/numerical/doc/watopt.3f
SEE ALSO
     [1] R. Chadha, K. Singhal, and J. Vlach, "WATOPT - A new
     optimizer  for circuit applications," in Proc. 1983 IEEE
     Int. Symp. Circuits Syst., pp. 1046 - 1049.
     [2] M.J.D.Powell, "A fast algorithm for nonlinearly con-
     strained optimization calculations," in: G.A.Watson, ed.,
     Numerical Analysis, Dundee, 1977, Lecture notes in Mathemat-
     ics 630 (Springer-Verlag, Berlin, 1978) pp. 144 - 157.
Printed 7/28/83          WATENG 83-7-28                         5