add contraints on parameters defined in function

3 次查看（过去 30 天）

显示更早的评论

Giru Mishra 2018-1-19

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/377925-add-contraints-on-parameters-defined-in-function

评论： Matt J 2018-1-20

采纳的回答： Walter Roberson

I have a function:

y =x.^a + z.^b

For which I wrote a separate function as I neet to fit it over my data. But I want to add constraint: a>b. How will I do that? Please help me with it. Thanks

5 个评论
显示 3更早的评论隐藏 3更早的评论

Torsten 2018-1-19

Use "lsqcurvefit" together with the model function y=Const*(x^(c1+c2)+z^c1) and include the bound constraint c2>0.

Once lsqcurvefit has determined c1 and c2, a=c1+c2 and b=c1 in your original model.

Best wishes

Torsten.

Giru Mishra 2018-1-19

any other way?

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Walter Roberson 2018-1-19

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/377925-add-contraints-on-parameters-defined-in-function#answer_300907

在 MATLAB Online 中打开

if a > b
  y = x.^a + z.^b;
else
  y = zeros(size(x));
end

4 个评论
显示 2更早的评论隐藏 2更早的评论

Giru Mishra 2018-1-20

Thanks Walter and Torsten... It was really very helpful..

Matt J 2018-1-20

@Giru,

You should Accept-click the answer if it helped you.

请先登录，再进行评论。

类别

AI and Statistics Curve Fitting Toolbox Get Started with Curve Fitting Toolbox

在 Help Center 和 File Exchange 中查找有关 Get Started with Curve Fitting Toolbox 的更多信息

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by