Filter löschen
Filter löschen

How to get the fitted data by using Matlab's "Fit" Function?

18 Ansichten (letzte 30 Tage)
Zheng am 21 Sep. 2012
For example, by using below code
load franke;
fitresult = fit( [x, y], z, 'poly33' );
From fitresult, I can get the formula used to fit x,y and z data
But how can I get the fitted data matrix via this "fit" function?

Akzeptierte Antwort

Wayne King
Wayne King am 22 Sep. 2012
It gives you a 1-D vector, but that 1-D vector is a polynomial in two variables, hence it is a function of the form f(x,y)=z
shows you exactly what the terms in x and y the coefficients multiply

Weitere Antworten (1)

Wayne King
Wayne King am 22 Sep. 2012
Hi, you can use the coeffvalues() method on the fitresult object.
coeffs = coeffvalues(fitresult);
That will give you the coefficients of your polynomial in x and y.
To see how those coefficients enter into the polynomial equation:
  2 Kommentare
Zheng am 22 Sep. 2012
Thanks, Wayne. But how can I use this formula to calculate the surface (shown as below)? This formula can only help me get a 1-D vector, not 2-D matrix.
grace am 22 Feb. 2013
May I know what is the code for goodness of fit? coeffs = coeffvalues(fitresult); Similarly, rsquare = code(fitresult); I wanted to get the rsquare values from cftool to display in command window.

Melden Sie sich an, um zu kommentieren.


Mehr zu Get Started with Curve Fitting Toolbox finden Sie in Help Center und File Exchange

Community Treasure Hunt

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

Start Hunting!

Translated by