本人毕业论文需要计算一个最优化的方程并估计相关的参数，相关模型如下，但运行的时候发生错误，错误代码：63；错误信息：Model is ill defined. Check for undefined indices and/or conditions in expression:16。麻烦高手帮忙解答。（附件是相应的优化模型和lingo程序的压缩包）

model:

SETS:

first/1..13/:M,Mn,Mp,Yn,Ym,W;

second/1..13/:Vn,V0n,Vp,V0p,V,EXp;

assign(first,second):Xdn,Xdp,Xmn,Xmp,X,X0dn,X0dp,X0mn,X0mp;

ENDSETS

data:

X0mp=@file(data1.txt);

X0mn=@file(data2.txt);

X0dn=@file(data3.txt);

X0dp=@file(data4.txt);

EXp=@file(EXp.txt);

Ym=@file(Ym.txt);

Yn=@file(Yn.txt);

Mp=@file(Mp.txt);

Mn=@file(Mn.txt);

V=@file(V.txt);

M=@file(M.txt);

W=@file(W.txt);

V0n=@file(V0n.txt);

V0p=@file(V0p.txt);

X=@file(Xij.txt);

enddata

min=@sum(assign(i,j):(Xdn(i,j)-X0dn(i,j))^(2)/X0dn(i,j))+@sum(assign(i,j):(Xdp(i,j)-X0dp(i,j))^(2)/X0dp(i,j))+@sum(assign(i,j):

(Xmn(i,j)-X0mn(i,j))^(2)/X0mn(i,j))+@sum(assign(i,j):(Xmp(i,j)-X0mp(i,j))^(2)/X0mp(i,j))+@sum(second(j):(Vn(j)-V0n(j))^(2)/V0n(j))

+@sum(second(j):(Vp(j)-V0p(j))^(2)/V0p(j));

@for(first(i):@sum(second(j):Xdn(i,j)+Xdp(i,j))+Yn(i)=W(i)-EXp(i));

@for(first(i):@sum(second(j):Xmn(i,j)+Xmp(i,j))+Ym(i)=M(i));

@for(second(j):@sum(first(i):Xdn(i,j)+Xmn(i,j))+Vn(j)=W(j)-EXp(j));

@for(second(j):@sum(first(i):Xdp(i,j)+Xmp(i,j))+Vp(j)=EXp(j));

@for(second(j):Vn(j)+Vp(j)=V(j));

@for(assign(i,j):Xdn(i,j)+Xdp(i,j)+Xmn(i,j)+Xmp(i,j)=X(i,j));

@for(first(i):@sum(second(j):Xmn(i,j))=Mn(i));

@for(first(i):@sum(second(j):Xmp(i,j))=Mp(i));

@for(first(i):@sum(second(j):Xdn(i,j)+Xdp(i,j)-X(i,j))=-Mn(i)-Mp(i));

@free(Xdn(i,j));@free(Xdp(i,j));@free(Xmn(i,j));@free(Xmp(i,j));@free(Vn(j));@free(Vp(j));

end