[求助]fminsearch应用出错 [复制链接]

我的M文件如下： 1f~unb\Gg  
function [G5]=fun(x); 8.{5c6G  
syms n1 n2 k1 k2 d; >Ah [uM  
[subwave,nsub]=textread('subout.txt','%f %f'); <3O>  
[filmwave,filmtran]=textread('filmtr.dat','%f %f'); !j%v
Ue;t  
[p,q]=size(subwave); -?2ThvT  
for j=1:p; {]Nvq9?  
    wavel(j)=subwave(j,1); |"5NI'X?  
    n(j)=n1+n2/((wavel(j))^2); h[ba$S,T  
    k(j)=k1*exp(k2/wavel(j)); p8%x@%k  
    N(j)=n(j)-i*k(j); SEIGs_^'\  
    phase(j)=2*pi*N(j)*d/wavel(j); p
r(:99~3  
    ns(j)=nsub(j,1); ~U~
KUL|  
    B(j)=cos(phase(j))+ns(j)*i*sin(phase(j))/N(j); .N5}JUj  
    C(j)=i*N(j)*sin(phase(j))+ns(j)*cos(phase(j)); Jq<&`6hn  
    T(j)=4*ns(j)/((B(j)+C(j))*conj(B(j)+C(j))); ;pBSGr9  
    ts(j)=1-((1-ns(j))/(1+ns(j)))^2; vtCt6M  
    t1(j)=ts(j)*T(j); [,8@oM#  
    tf(j)=filmtran(j,1)/100; -%5*c61  
    difference(j)=(t1(j)-tf(j))^2; ?\(E+6tpP  
end %%G2w63M  
G=symsum(difference(j),1,401); &Jk0SUk MP  
G1=subs(G,n1,sym('x(1)')); owmV7E
1  
G2=subs(G1,n2,sym('x(2)')); +a"MSPC4w  
G3=subs(G2,k1,sym('x(3)')); A=I]1r  
G4=subs(G3,k2,sym('x(4)')); 1bYc^(z0  
G5=subs(G4,d,sym('x(5)')); ['tGc{4  
Cc$!TZq=  
?Z.p.v  
kHo0I8  
在matlab下运行 Q
O[!  
>> options=optimset('tolfun',1e-8,'tolx',1e-8); g&`e2|[7  
>> [xmin,value,flag,output]=fminsearch(@fun,[1.7,4000,0.005,400,500],options); GXYmJ4wR  
HIk5Q'ek  
Kxn/@@z>u  
结果出错如下：
-ce N}Cb3  
/v U$62KA  
??? Conversion to double from sym is not possible. jdK~]eld=  
Error in ==> fminsearch at 175 B~D{p t3y  
fv(:,1) = funfcn(x,varargin{:}); E2Q;1Re@  
K#%L6=t$<  
哪位高手给看看 =$X5O&E3'  

哪位高人告诉我，错误在哪里呀。M文件复制到命令行，执行，一切正常，就是在求解多元函数0值时，不知道哪里错了。 ^ r-F@$:.  
P(l$5x]g,  
EcxPbRg  
万分感谢呀