SQIC is a software package for minimizing a general quadratic function subject to both equality and inequality constraints. SQIC is an implementation of an inertia-controlling active-set method that is capable of utilizing third-party linear solvers. It is efficient on problems with a small or large number of degrees of freedom.
SQIC is intended for large-scale problems with sparse Hessian and constraint matrices. The quadratic term 1/2 x'Hx in the objective function is represented by either a user subroutine that returns the product Hx for a given vector x, or a sparse matrix structure containing the matrix H.