//This problem solves sustem of nonlinear equations using fsolve //Reference: A. Golbabai, M. Javidi,Newton-like iterative methods for solving system of non-linear equations,Applied Mathematics and Computation,Volume 192, Issue 2,2007,Pages 546-551,ISSN 0096-3003,https://doi.org/10.1016/j.amc.2007.03.035.(http://www.sciencedirect.com/science/article/pii/S0096300307003578) //====================================================================== // Copyright (C) 2018 - IIT Bombay - FOSSEE // This file must be used under the terms of the CeCILL. // This source file is licensed as described in the file COPYING, which // you should have received as part of this distribution. The terms // are also available at // http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt // Author:Debasis Maharana // Organization: FOSSEE, IIT Bombay // Email: toolbox@scilab.in //====================================================================== clc //Function representing system of nonlinear equaltions function f = SLEs(p) x = p(1);y = p(2); f(1) = (x+10)/x^4 + x^2 + 3*x*y + y^2-16; f(2) = 1/(x+y)^7 + x*y - 1 - 1/2^7; endfunction //Tolarence of solution tol = 1D-15; //Initial guess x0 = [10 10]; disp(x0,'Initial guess value is'); //Obtaining solution using fsolve [x ,v ,info] = fsolve(x0,SLEs,tol) clc select info case 0 mprintf('\n improper input parameters\n'); case 1 mprintf('\n algorithm estimates that the relative error between x and the solution is at most tol\n'); case 2 mprintf('\n number of calls to fcn reached\n'); case 3 mprintf('\n tol is too small. No further improvement in the approximate solution x is possible\n'); else mprintf('\n iteration is not making good progress\n'); end disp(x,'The solution is ') disp(v,'the function value at solution')