In this paper, the authors describe and establish the convergence of a
new iterative method for solving the (nonmonotone) nonlinear compleme
ntarity problem (NCP). The method utilizes ideas from two distinct app
raoches for solving this problem and combines them into one unified fr
amework. One of these is the infeasible-interior-point approach that c
omputes an approximate solution to the NCP by staying in the interior
of the nonnegative orthant; the other approach is typified by the NE/S
QP method which is based on a generalized Gauss-Newton scheme applied
to a constrained nonsmooth-equations formulation of the complementarit
y problem. The new method, called a positive algorithm for the NCP, ge
nerates a sequence of positive vectors by solving a sequence of linear
equations (as in a typical interior-point method) whose solutions (if
nonzero) provide descent directions for a certain merit function that
is derived from the NE/SQP iteration function modified for use in an
interior-point context.