Dennis, J.E. Jr.Gay, David M.Vu, Phuong Ahn2018-06-182018-06-181983-06Dennis, J.E. Jr., Gay, David M. and Vu, Phuong Ahn. "A New Nonlinear Equations Test Problem." (1983) <a href="https://hdl.handle.net/1911/101557">https://hdl.handle.net/1911/101557</a>.https://hdl.handle.net/1911/101557This presents a set of test problems for nonlinear equations and nonlinear least-squares algorithms. These problems, sent to us by C.V. Nelson of the Maine Medical Center, come from a dipole model of the heart. They are 6 x 6 or 8 x 8, easy to code, cheap to evaluate, and not easy to solve. In support of the latter contention, we present test results from MINPACK AND NL2SOL.12 ppengTechnical reportTR83-16