borgar

/**
 * Searches the interval from <tt>lowerLimit</tt> to <tt>upperLimit</tt>
 * for a root (i.e., zero) of the function <tt>func</tt> with respect to 
 * its first argument using Brent's method root-finding algorithm.
 *
 * Translated from zeroin.c in http://www.netlib.org/c/brent.shar.
 *
 * Copyright (c) 2012 Borgar Thorsteinsson <borgar@borgar.net>
 * MIT License, http://www.opensource.org/licenses/mit-license.php
 *