Nlinfit error with func2str
3 次查看(过去 30 天)
显示 更早的评论
Hello,
I am trying to fit a curve using this function: t is the time vector, x the force measurement, d0 and nu are constants. I want to extract Er, tau1 and tau2.
function [Er,tau1,tau2] = viscoelasticcone(t,x,d0,nu)
fitfunctionconical=sprintf('Er*2*tan(35*pi/180)/(pi*(1-%d^2))*%d^2*(1+(tau1-tau2)/tau2*exp(-t/tau2))',nu,d0);
ftconical=fittype( fitfunctionconical, 'independent', 't', 'dependent', 'F');
[fitresult,R,~,CovB,MSE] = nlinfit(t,x, ftconical,[1e3 0.001 0.001]);
fit=ftconical(fitresult,t);
[Ypred,delta] = nlpredci(ftconical,t,fitresult,R,'Covar',CovB,'MSE',MSE,'SimOpt','on');
confidence{k}=delta;
lower = Ypred - delta;
upper = Ypred + delta;
end
If I use this function however, i get the following error:
Undefined function 'func2str' for input arguments of type 'fittype'.
Error in nlinfit (line 204)
m = message('stats:nlinfit:ModelFunctionError',func2str(model));
Any help ?
Michael
0 个评论
采纳的回答
Walter Roberson
2015-8-11
You need to call fit() on fit objects returned from fittype(), not nlinfit()
2 个评论
更多回答(0 个)
另请参阅
类别
在 Help Center 和 File Exchange 中查找有关 Fit Postprocessing 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!