请问，lsqcurvefit拟合后如何显示相关系数R^2？

limopcb

$ C  c& d/ d: J! d( i: A* ^" Z3 T请问，lsqcurvefit拟合后如何显示相关系数R^2，感谢！
* I; R; d* k* Z* a, zclear;clc;
T=[293.15        298.15        303.15        308.15        313.15];
4 F( k4 A# y* f% E# Nc=[0.000378156        0.000425433        0.000562474        0.000684178        0.000981096];
: z" Y% h( y% J, s5 ^. z1 WTT=T';
cc=c';
x=[TT,cc];
Hm=33509;
& N5 k: _6 _; q* V, xTm=408.65;
a=0.3;
fun=@(q,x)(-Hm.*(x(:,1)./Tm-1)./(8.314.*x(:,1))+log(x(:,2))+(1-x(:,2)).^2.*((q(1)./(8.314.*x(:,1))).*(exp(-a.*q(1)./(8.314.*x(:,1)))./(x(:,2)+(1-x(:,2)).*exp(-a.*q(1)./(8.314.*x(:,1))))).^2+(q(2)./(8.314.*x(:,1))).*exp(-a.*q(2)./(8.314.*x(:,1)))./(1-x(:,2)+x(:,2).*exp(-a.*q(2)./(8.314.*x(:,1)))).^2));
q0=[0,0];
q=lsqcurvefit(fun,q0,x,zeros(size(x,1),1))
plot(x(:,1),x(:,2),'r^');hold on;
ezplot(@(x,c)fun(q,[x,c]),[290,314,0.0003,0.001]);
- n/ }+ m5 N8 M7 Ph=ezplot(@(x,c)fun(q,[x,c]),[290,314,0.0003,0.001]);
6 Z7 Y: o2 Y7 X4 Q

Allevi

非线性拟合，R2没有意义的
& g) `. q) [$ F参考
& g, z3 T* g" \# W6 x- q/ Rstatisticsbyjim.com/regression/r-squared-invalid-nonlinear-regression
  K9 }3 y- R1 _blog.minitab.com/blog/adventures-in-statistics-2/why-is-there-no-r-squared-for-nonlinear-regression