如下问题如何解决

cumtmbqq

如下代码，我要会出u随着b的变化曲线，现在通过solve求解出了u表达式中各个系数，再带入x，y值就可以了，可是为什么老出错啊
clc;
clear;
syms x a b y A1 A2 E1 E2 B u v j1 j2 q
E2=0
E1=2.5e9
j2=0.3
j1=0.25
a=2.5
q=18e6
u=x*(a+b-x)*(y-a)^2*(A1+A2*x);
v=B*y;
uu1=j1/(1-2*j1)*((diff(u,x)+diff(v,y))^2+(diff(u,x))^2+(diff(v,y))^2+0.5*(diff(v,x)+diff(u,y))^2);
uu2=j2/(1-2*j2)*((diff(u,x)+diff(v,y))^2+(diff(u,x))^2+(diff(v,y))^2+0.5*(diff(v,x)+diff(u,y))^2);
w1=int(uu1,x,0,b);
w2=int(uu2,x,b,a+b);
u1=int(w1,y,0,a)*E1/(2*(1+j1));
u2=int(w2,y,0,a)*E2/(2*(1+j2));
uu=u1+u2;

q1=diff(uu,A1);
q2=diff(uu,A2);
q3=diff(uu,B)+2*q*a/(E1+E2)*(b*E1+a*E2);
[A1,A2,B]=solve(q1,q2,q3,A1,A2,B)
x=b
y=0
ezplot(u,[5,50])

Walker0728

我觉得你因该写成类似于 ezplot('x.*y + x.^2 - y.^2 - 1')的格式，并且要注意你所操作的数据的类型