  We present a short step interior point method for solving a class of
nonlinear programming problems with quadratic objective function. Convex
quadratic programming problems can be reformulated as problems in this class.
The method is shown to have weak polynomial time complexity. A complete proof
of the numerical stability of the method is provided. No requirements on
feasibility, row-rank of the constraint Jacobian, strict complementarity, or
conditioning of the problem are made. Infeasible problems are solved to an
optimal interior least-squares solution.
