exm040107.m

来自「matlab电子书籍」· M 代码 · 共 19 行

syms x
y=(x+pi)*exp(abs(sin(x+pi)));
yd=diff(y,x);						
xs0=solve(yd)						
yd_xs0=vpa(subs(yd,x,xs0),6)	
y_xs0=vpa(subs(y,x,xs0),6)		
y_m_pi=vpa(subs(y,x,-pi/2),6)	
y_p_pi=vpa(subs(y,x,pi/2),6)	

x1=-pi/2;x2=pi/2;						
yx=@(x)(x+pi)*exp(abs(sin(x+pi)));	
[xn0,fval,exitflag,output]=fminbnd(yx,x1,x2)

xx=-pi/2:pi/200:pi/2;					
yxx=(xx+pi).*exp(abs(sin(xx+pi)));
plot(xx,yxx)
xlabel('x'),grid on

[xx,yy]=ginput(1)