Regression curve fitting for a given equation

Find the best fit by given equation
x = [0.0191051892041436 0.0199064802088661 0.0205144445903776 0.0210029746368803 0.0216434799932356 0.0226870689634767 0.0238694334820173 0.0247271126862428 0.0255324218699147 0.0266869614901355];
y = [0.726909090909091 0.731030303030303 0.730909090909091 0.709818181818182 0.664424242424242 0.621454545454545 0.606848484848485 0.597151515151515 0.595939393939394 0.583333333333333];
plot(x, y, 'b.-');
grid on;
where y = (x/a)*ln((m-1)/b) +y0

 채택된 답변

Matt J
Matt J 2023년 6월 12일
편집: Matt J 2023년 6월 12일

0 개 추천

p=polyfit(x,y,1);
From this, you immediately obtain y0=p(2). For the remaining parameters, you can choose any of the infinite solutions to ln((m-1)/b)/a=p(1).

댓글 수: 2

Arvind
Arvind 2023년 6월 12일
i have want all values like m, b and a separetly
@Arvind, the equation you want to fit to,
y = (x/a)*ln((m-1)/b) + y0
is equivalent to
y = x*c + y0
where
c = (1/a)*ln((m-1)/b)
The solution that @Matt J provided is solving for y0 and what I called c.
It is not possible (without other restrictions) to determine what a, m, and b are. As Matt stated, there are literally an infinite combination of possibilities.

댓글을 달려면 로그인하십시오.

추가 답변 (0개)

카테고리

도움말 센터File Exchange에서 Get Started with Curve Fitting Toolbox에 대해 자세히 알아보기

제품

릴리스

R2023a

질문:

2023년 6월 12일

댓글:

2023년 6월 12일

Community Treasure Hunt

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

Start Hunting!

Translated by