Back Mètodes quasi-Newton Catalan Quasi-Newton-Verfahren German Méthode quasi-Newton French 準ニュートン法 Japanese Metoda quasi-Newtona Polish Квазиньютоновские методы Russian Квазі-ньютонів метод Ukrainian 擬牛頓法 Chinese
Quasi-Newton methods are methods used to find either zeroes or local maxima and minima of functions, as an alternative to Newton's method. They can be used if the Jacobian or Hessian is unavailable or is too expensive to compute at every iteration. The "full" Newton's method requires the Jacobian in order to search for zeros, or the Hessian for finding extrema. Some iterative methods that reduce to Newton's method, such as SLSQP, may be considered quasi-Newtonian.