matlab函数参数不足 调用函数显示输入参数不足

问题描述.png (29.7 KB, 下载次数: 1)

-1-27 09:34 上传

%Gauss-Newton算法实现如下

function[x,minf] = GN(f,x0,var,eps)formatlong;

ifnargin == 3%如果没有设置eps，则eps=1.0e-6eps = 1.0e-6;

end

m = 0;

S =transpose(f)*f; %trnspose是转置,求得r方k =length(f);%

%n =length(x0);%n为变量个数,但是没用到啊？x0 =transpose(x0); %将行向量转置为列向量tol =1; %初始容差A =jacobian(f,var);

whiletol>eps

Fx = zeros(k,1);

for i=1:k

Fx(i,1) = subs(f(i),var,x0);

end

Sx = subs(S,var,x0); %求得f转置与其本身值，Ax = subs(A,var,x0); %雅克比矩阵的值gSx = transpose(Ax)*Fx;

dx = -transpose(Ax)*Ax\gSx;

x0 = x0 + dx;

tol = norm(dx); %tol=dx绝对值之和m = m+1;

if(m>100000)

disp('迭代步数太多，可能不收敛');return;

end

end

minf =subs(S,var,x);

formatshort;

x = x0;

end

调用如下：

>> syms z1 z2 z3 z4 z5

>> x0 =[1.7380;0.9555;-1.3863;2.0149;-2.5257];

>> R =exp(z1)./(exp(z1)+exp(-z1)).*exp(-(xdata./exp(z3)).^exp(z2))+(1-exp(z1)./(exp(z1)+exp(-z1))).*exp(-(xdata./exp(z5)).^exp(z4));

>> f = 0.5.*(ydata1 - R).^2;

>> var = findsym(f);

>> eps = 1.0e-3;

>> GN(f,x0,var,eps)

出现问题如下：

从 sym 转换为 double 时出现以下错误:

出错 GN (line 17)

Fx(i,1) = subs(f(i),var,x0);%subs(f(i),var,x0);