作业帮matlab求解优化问题 采用非线性最小二乘法 lsqnonlin函数 编程遇到问题采用lsqnonlin函数 编写的一个函数m文件如下：function F=myfun3(a)i=1:5;mi=[0.0686,1.0714,0.0714,3.2445,-0.0798];syms x;t=a(1)*x+a(2)*x^2+a(3)*x^3+
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![matlab求解优化问题 采用非线性最小二乘法 lsqnonlin函数 编程遇到问题采用lsqnonlin函数 编写的一个函数m文件如下：function F=myfun3(a)i=1:5;mi=[0.0686,1.0714,0.0714,3.2445,-0.0798];syms x;t=a(1)*x+a(2)*x^2+a(3)*x^3+](/uploads/image/z/15096591-63-1.jpg?t=matlab%E6%B1%82%E8%A7%A3%E4%BC%98%E5%8C%96%E9%97%AE%E9%A2%98+%E9%87%87%E7%94%A8%E9%9D%9E%E7%BA%BF%E6%80%A7%E6%9C%80%E5%B0%8F%E4%BA%8C%E4%B9%98%E6%B3%95+lsqnonlin%E5%87%BD%E6%95%B0+%E7%BC%96%E7%A8%8B%E9%81%87%E5%88%B0%E9%97%AE%E9%A2%98%E9%87%87%E7%94%A8lsqnonlin%E5%87%BD%E6%95%B0+%E7%BC%96%E5%86%99%E7%9A%84%E4%B8%80%E4%B8%AA%E5%87%BD%E6%95%B0m%E6%96%87%E4%BB%B6%E5%A6%82%E4%B8%8B%EF%BC%9Afunction+F%3Dmyfun3%28a%29i%3D1%3A5%3Bmi%3D%5B0.0686%2C1.0714%2C0.0714%2C3.2445%2C-0.0798%5D%3Bsyms+x%3Bt%3Da%281%29%2Ax%2Ba%282%29%2Ax%5E2%2Ba%283%29%2Ax%5E3%2B)
matlab求解优化问题 采用非线性最小二乘法 lsqnonlin函数 编程遇到问题采用lsqnonlin函数 编写的一个函数m文件如下：function F=myfun3(a)i=1:5;mi=[0.0686,1.0714,0.0714,3.2445,-0.0798];syms x;t=a(1)*x+a(2)*x^2+a(3)*x^3+
matlab求解优化问题 采用非线性最小二乘法 lsqnonlin函数 编程遇到问题
采用lsqnonlin函数
编写的一个函数m文件如下：
function F=myfun3(a)
i=1:5;
mi=[0.0686,1.0714,0.0714,3.2445,-0.0798];
syms x;
t=a(1)*x+a(2)*x^2+a(3)*x^3+a(4)*x^4+a(5)*x^5;
f=(1+t+t^2/2+t^3/6+t^4/24+t^5/120);
F=1-int(x.^i*f,x,-3,3)/mi*(int(f,x,-3,3));
然后再命令窗口输入 如下命令：
>> a0=[0,0,0,0,0];
>> [a,resnorm]=lsqnonlin(@myfun3,a0)
然后运行
结果出现一堆看不懂的问题：
好几个warning 如 Warning:System is inconsistent.Solution does not exist.
> In sym.mldivide at 32
In sym.mrdivide at 27
In myfun3 at 7
In optim\private\lsqncommon at 88
In lsqnonlin at 163
还有如下错误 Function 'lt' is not defined for values of class 'sym'.
Error in ==> optim\private\nlsq at 329 if (GradF'*SD) < tolFun && ...
Error in ==> optim\private\lsqncommon at 216 [x,FVAL,JACOB,EXITFLAG,OUTPUT,msg] = ...
Error in ==> lsqnonlin at 163[x,Resnorm,FVAL,EXITFLAG,OUTPUT,LAMBDA,JACOB] = ...
matlab不是很懂,麻烦高人看看我的程序怎么改,
matlab求解优化问题 采用非线性最小二乘法 lsqnonlin函数 编程遇到问题采用lsqnonlin函数 编写的一个函数m文件如下：function F=myfun3(a)i=1:5;mi=[0.0686,1.0714,0.0714,3.2445,-0.0798];syms x;t=a(1)*x+a(2)*x^2+a(3)*x^3+
这是我修改以后的程序
%%%%%%%%%
function F = myfun3(x)
p=1:5;
m=[0.0686,1.0714,0.0714,3.2445,-0.0798];
syms k t f;
t=x(1)*k+x(2)*k^2+x(3)*k^3+x(4)*k^4+x(5)*k^5;
f=1+t+t^2/2+t^3/6+t^4/24+t^5/120;
F=1-eval(int(k.^p*f,k,-3,3))./m(p)*(eval(int(f,k,-3,3)));
end
%%保存为M文件
%%%%%%%%%
%%命令窗口中输入
clc
tic
x0=[0,0,0,0,0];
[x,resnorm]=lsqnonlin(@myfun3,x0)
toc
%%结果为
x =
0.0493 -0.9723 -0.0156 0.0932 0.0012
resnorm =
2.4422e-027
Elapsed time is 123.737320 seconds.
%%程序运行了123秒啊,我还是第一次见过这么长的运算时间!