.. _glossary: Glossary ======== Technical terms used in the lab assignment material. .. glossary:: Newton-Raphson method (also known as Newton's method) is an algorithm to **find the root** of a function (i.e. find :math:`x` such that :math:`f(x)=0`). In particular, it is a popular method to solve the AC power flow equations (default method in MATPOWER, see ยง4.1 of the manual [MATPOWER-man]_). It proceeds in an iterative manner, starting from an initial guess :math:`x_0` (provided by the user). This guess is refined with a linear approximation of the function, using the knowledge of the gradient :math:`f'(x)`) .. math:: x_{n+1} = x_n - \frac{f(x_n)}{f'(x_n)} see e.g. Wikipedia for a graphical animation of the method in 1D https://en.wikipedia.org/wiki/Newton's_method