初学matlab编程遇到的问题

yuskiy

h1=0.01;
N=17;
M_8=2;
u=0.01;
Nx=100000
R_x=Nx*(a1^2)/d3
R_y=d1*(h1^2)/2/d3;
a1=1;
b1=1;
v1=0.3;
e1=106*(10^9);
e2=251*(10^9);
i1=1;
syms y;
p1=(e1-e2)*((2*y+h1)/2/h1)^i1+e2;
d1=int(p1/(1-v1^2),y,-h1/2,h1/2) ;
d2=int(p1*y/(1-v1^2),y,-h1/2,h1/2);
d3=int(p1*(y^2)/(1-v1^2),y,-h1/2,h1/2);
for vv=0:1:9999;   
v=vv/d3;
for i=1:N-4
      Gdb(i,2)=(u*v/M_8)^(1/2);
end
end
出现问题：Conversion to double from sym is not possible.
问题应该是出在d3这个值上，希望有高手能指点一下如何修改。

wadaxi74144

syms y;
h1=0.01;
a1=1;
b1=1;
v1=0.3;
e1=106*(10^9);
e2=251*(10^9);
i1=1;
N=17;
M_8=2;
u=0.01;
Nx=100000
p1=(e1-e2)*((2*y+h1)/2/h1)^i1+e2;
d1=int(p1/(1-v1^2),y,-h1/2,h1/2) ;
d2=int(p1*y/(1-v1^2),y,-h1/2,h1/2);
d3=int(p1*(y^2)/(1-v1^2),y,-h1/2,h1/2);
R_x=Nx*(a1^2)/d3
R_y=d1*(h1^2)/2/d3;
for vv=0:1:9999;   
v=vv/d3;
for i=1:N-4
      Gdb(i,2)=(u*v/M_8)^(1/2);
end
end

程序弄好了  你编程序的时候  要用的变量需先出现  要不就说你没定义