Question

用matlab拟合函数

x=[0.0318,0.0208,0.0148,0.00974,0.00744,0.00574,0.00424,0.00339,0.00279,0.00221,0.00186,0.00161,0.00136,0.00121,0.00109,0.000963]';
y=[10,20,40,100,200,400,1000,2000,4000,10000,20000,40000,100000,200000,400000,1000000]';
要拟合成这种形式：(a/165000)*(2*x)^b+d*(2*x)^c，要确定a,b,c,d
看了很多人的评论，但自己总是出不来结果
大神帮一下吧！

Answer 1

用matlab拟合成：(a/165000)*(2*x)^b+d*(2*x)^c这种形式，一般可以lsqcurvefit（）来确定a,b,c,d的系数。

经拟合可以求得

a=0.00011353,b=1,c=-5.1844,d=-5.1844

R^2=0.97664    %相关系数（拟合度）

运行代码：

追问

大神你好，非常感谢你的回答，但是我好像方程给错了。。。应该是x=(a/165000)*(2*y)^b+d*(2*y)^c，您能不能帮我再算一下啊。。。我用你的代码总是出现solver stopped prematurely是什么情况？