get mean and std from sfit object

Question

Reto Hofmann 2014-4-1

0
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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/124034-get-mean-and-std-from-sfit-object

回答： Reto Hofmann 2014-4-1

I use poly55 for fitting a surface to my measurement data. The result is a sfit object from which I can extract the coefficients with coeffvalues(fitresults):

% Set up fittype and options.
ft = fittype( 'poly55' );
% Fit model to data.
[fitresult, gof] = fit( [xData, yData], zData, ft, 'Normalize', 'on' );

In the command Windowc comes:

     Linear model Poly55:
     fitresult(x,y) = p00 + p10*x + p01*y + p20*x^2 + p11*x*y + p02*y^2 
                    + p30*x^3 + p21*x^2*y + p12*x*y^2 + p03*y^3 + p40*x^4 
                    + p31*x^3*y + p22*x^2*y^2 + p13*x*y^3 + p04*y^4 + p50*x^5 
                    + p41*x^4*y + p32*x^3*y^2 + p23*x^2*y^3 + p14*x*y^4 
                    + p05*y^5
       where x is normalized by mean 948.8 and std 307.3
       and where y is normalized by mean 474.7 and std 226.8
     Coefficients (with 95% confidence bounds):
       p00 =       3.329  (3.271, 3.386)
       p10 =     -0.7384  (-0.8502, -0.6267)
       p01 =      -13.96  (-14.08, -13.83)
       p20 =       1.843  (1.762, 1.923)
       p11 =     -0.1893  (-0.2839, -0.09466)
       p02 =     -0.2026  (-0.3119, -0.0933)
       p30 =      0.1761  (0.07422, 0.2779)
       p21 =       0.971  (0.8428, 1.099)
       p12 =      0.0674  (-0.06616, 0.201)
       p03 =      0.1113  (-0.03479, 0.2573)
       p40 =     -0.1148  (-0.1391, -0.09059)
       p31 =     0.02515  (-0.00647, 0.05677)
       p22 =     0.06291  (0.02904, 0.09678)
       p13 =    0.002115  (-0.03754, 0.04177)
       p04 =     0.03172  (-0.01116, 0.0746)
       p50 =    -0.02834  (-0.05165, -0.005038)
       p41 =    -0.05022  (-0.08373, -0.01672)
       p32 =   0.0001545  (-0.03869, 0.03899)
       p23 =    -0.01278  (-0.04958, 0.02402)
       p14 =   -0.003341  (-0.04329, 0.03661)
       p05 =     0.03711  (-0.005346, 0.07957)