evcombustion(x)

function y = evcombustion(x)

% Name: Equilibrium Combustion
% Reference: 
% Handbook of Test Problems in Local and Global Optimization. C.A. Floudas,
% P. M. Pardalos, C.S. Adjiman, W. R. Esposito, Z.H. Gumus, S. T. Harding,
% J.L. Klepeis, C. A. Meyer, C. A. Schweiger. 1999. Kluwer Publishers.
% Variables: 5
% Initial Point/ Initial Interval: [10,..,10] /([0.0001,100],...,[0.0001,100])
% Matlab Code by Tiago Montanher (Mar. 06, 2009).

 R = 10;
 R5 = 0.193; 
 R6 = 4.10622*10^-4;
 R7 = 5.45177*10^-4;
 R8 = 4.4975*10^-7; 
 R9 = 3.40735*10^-5;
 R10 = 9.615*10^-7;
 
 if isintval(x)
  R = intval(R); R5 = intval(R5); R6 = intval(R6); R7 = intval(R7);
  R8 = intval(R8); R9 = intval(R9); R10 = intval(R10);
 end
 
 y1 = x(1)*x(2) + x(1) - 3*x(5);
 
 y2 = 2*x(1)*x(2) + x(1) + 3*R10*x(2)^2 + x(2)*x(3)^2 + R7*x(2)*x(3) + R9*x(2)*x(4)...
      +R8*x(2) - R*x(5);
  
 y3 = 2*x(2)*x(3)^2 + R7*x(2)*x(3) + 2*R5*x(3)^2 + R6*x(3) - 8*x(5);
 
 y4 = R9*x(2)*x(4) + 2*x(4)^2 - 4*R*x(5);
 
 y5 = x(1)*x(2) + x(1) + R10*x(2)^2 + x(2)*x(3)^2 + R7*x(2)*x(3) + R9*x(2)*x(4)...
      + R8*x(2) + R5*x(3)^2 + R6*x(3) + x(4)^2 - 1;
 
 y  = [y1, y2, y3, y4, y5];
end