Ratfor code for the primal-dual log barrier form of the interior point LP solver of Lustig, Marsten and Shanno, ORSA J Opt 1992.

Fortran 77 package for solving unconstrained and constrained optimization problems, systems of nonlinear equations, and nonlinear least-squares problems.

Fortran 77 codes for nondifferentiable, large-scale, or dense nonlinear optimization. Mostly under the GNU General Public License.

Nonlinear programming codes: SQP, least squares, multicriteria optimization, data fitting in ODEs, DAEs, PDEs, PDAEs.

Trust region Newton method for the solution of large bound-constrained optimization problems, by Chih-Jen Lin and Jorge More.

Subspace-searching simplex method for the unconstrained optimization of general multivariate functions, generalizing the Nelder-Mead simplex method.

Optimization codes at Netlib.

Fortran 77 code for solving nonlinear equations and nonlinear least squares problems. Five algorithmic paths each include a core subroutine and an easy-to-use driver. The algorithms proceed either from an analytic specification of the Jacobian matrix ...

Solves nonlinear optimization problems. [Commercial]

Fortran 90 package for finding approximate solutions of certain binary quadratic programs, currently including the Max-Cut and the Max-Bisection problems.