How to use fmincon for my function with 2 variables?

Question

Sanjal C C 2018-6-23

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/407074-how-to-use-fmincon-for-my-function-with-2-variables

编辑： Walter Roberson 2018-6-24

function [pointoftangency] = Tangentpoint(X,Y,amplitude)
ptf=amplitude*sin(2*pi*x./25)+((2*pi*amplitude/25)*cos(2*pi*x./25)*(X-x))-Y
end

and my constraint equation is

amplitude*sin(2*pi*x/25)=0;

How do I solve this using fmincon??

2 个评论
显示无隐藏无

Rik 2018-6-24

Have a read here and here. It will greatly improve your chances of getting an answer.

You can 'trick' fmincon by entering your variables as a vector into your function.

Walter Roberson 2018-6-24

Which are the two variables? You have X, Y, and amplitude as inputs to Tangentpoint, and your code also uses x as well. Your code computs ptf, but your function expects pointoftangency to be output.

What is it that needs to be minimized?

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2018-6-24

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/407074-how-to-use-fmincon-for-my-function-with-2-variables#answer_326002

编辑：Walter Roberson 2018-6-24

Assuming that it is ptf that needs to be minimized with X, Y, amplitude constants, then the solution is that ptf becomes arbitrarily small (towards negative infinity) as x approaches positive infinity, assuming the value 2*Pi*amplitude*(X-50*Z)*(1/25)-Y when x = 50*Z with Z being an integer.

ptf becomes arbitrarily small (towards negative infinity) as x approaches negative infinity when x = 50*Z+25 with Z being an integer.