www.gusucode.com > symbolic 源码程序 matlab案例代码 > symbolic/ThreeDPlotOfMultivariableSystemOfEquationsExample.m
%% 3D Plot of Multivariable System of Equations %% 1 syms x y z eqn1 = z == 10*(cos(x) + cos(y)); eqn2 = z == x+y^2-0.1*x^2*y; eqn3 = x+y-2.7 == 0; equations = [eqn1 eqn2 eqn3]; fimplicit3(equations) axis([0 2.5 0 2.5 -20 10]) title('System of Multivariate Equations') view(69, 28) caxis([-15 10]) %% 2 sol = vpasolve(equations); [sol.x sol.y sol.z] %% 3 vars = [x y z]; range = [0 1.5; 1.5 2.5; NaN NaN]; sol = vpasolve(equations, vars, range); [sol.x sol.y sol.z] %% 4 clear sol range = [0 3; 0 3; NaN NaN]; for i = 1:5 temp = vpasolve(equations, vars, range, 'random', true); sol(i,1) = temp.x; sol(i,2) = temp.y; sol(i,3) = temp.z; end sol %% 5 clf ax = axes; h = fimplicit3(equations); h(2).FaceAlpha = 0; h(3).FaceAlpha = 0; axis([0 2.5 0 2.5 -20 10]) hold on scatter3(sol(:,1),sol(:,2),sol(:,3),600,'yellow','X','LineWidth',2) title('Randomly found solutions in specified search range') cz = ax.Children; caxis([0 20]) view(69,28) hold off