www.gusucode.com > symbolic 源码程序 matlab案例代码 > symbolic/Ch2FindAsymptotesCriticalAndInflectionPointsExample.m
%% Find Asymptotes, Critical and Inflection Points %% Define a Function 1 syms x num = 3*x^2 + 6*x -1; denom = x^2 + x - 3; f = num/denom %% Define a Function 2 fplot(f) %% Find Asymptotes 1 roots = solve(denom) %% Find Maximum and Minimum 1 f1 = diff(f); crit_pts = solve(f1); %% Find Maximum and Minimum 2 fplot(f) hold on plot(double(crit_pts), double(subs(f,crit_pts)),'ro') title('Maximum and Minimum of f') text(-4.8,5.5,'Local minimum') text(-2,4,'Local maximum') hold off %% Find Inflection Point 1 f2 = diff(f1); inflec_pt = solve(f2); inflec_pt = inflec_pt(1); %% Find Inflection Point 2 fplot(f, [-9 6]) hold on plot(double(inflec_pt), double(subs(f,inflec_pt)),'ro') title('Inflection Point of f') text(-7,1,'Inflection point') hold off