Usage example for RK_stab_fun Boundary of stability domain of Heun's method
0001 % Usage example for RK_stab_fun 0002 % Boundary of stability domain of Heun's method 0003 0004 alpha = 1; 0005 b = [1 - 1/(2*alpha); 1/(2*alpha)]; 0006 c = [0; alpha]; 0007 A = [0 0; 0008 alpha 0]; 0009 [ R ] = RK_stab_fun( b,c,A ) 0010 [X,Y] = meshgrid(-2.5:0.1:0.5,-2:0.1:2); 0011 Z = X+1i*Y; 0012 Rmod = abs(R); 0013 Rmod = matlabFunction(Rmod); 0014 boundary = feval(Rmod,Z); 0015 contour(X,Y,boundary,[1 1]); 0016 grid on; 0017 title(['Heun',char(39),'s rule']);