MANPAK: A set of algorithms for computations on implicitly defined manifolds. A collection of algorithms is presented for performing a variety of numerical tasks on general implicitly defined (by a system of underdetermined equations) submanifolds of a finite-dimensional space. This includes algorithms for determining local parametrizations and their derivatives, and for evaluating quantities related to the curvature with sensitivity measures. The methods have been implemented as a FORTRAN 77 package, called MANPAK. (netlib contin)