作者ksr310135 (馨右小小)
看板MATLAB
標題Re: Curve fitting 不用toolbox求解
時間Tue Sep 13 18:12:37 2016
Signal=[23.6360000000000
14.0574000000000
6.72888000000000
3.86307000000000
2.54284000000000
2.01951000000000
1.76490000000000
1.55241000000000
1.44080000000000
1.37599000000000
1.31569000000000
1.27775000000000
1.23654000000000
1.20946000000000
1.19213000000000];
echotime=[7.73700000000000
13.3570000000000
18.9770000000000
24.5970000000000
30.2170000000000
35.8370000000000
41.4570000000000
47.0770000000000
52.6970000000000
58.3170000000000
63.9370000000000
69.5570000000000
75.1770000000000
80.7970000000000
86.4170000000000];
F1=@(x,xdata) x(1)+x(2)*exp(-xdata/x(3));
x0=[1.2061 56.4124 8.5219]; % initial guess
[x1,resnorm,~,exitflag,output]=lsqcurvefit(F1,x0,echotime,Signal);
F2=@(x,xdata) x(1)+x(2)*exp(-xdata/x(3))+(1-x(4))*exp(-xdata/x(5));
x0=[1.2061 0.0315 0.1255 -55.4127 8.5219]; % initial guess
[x2,resnorm,~,exitflag,output]=lsqcurvefit(F2,x0,echotime,Signal);
x1
x2
plot(echotime,Signal,'ro',echotime,F1(x1,echotime),'-',echotime,F2(x2,echotime),'--')
legend('data','fit 1','fit 2')
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1F：推 hanhan3431: 為什麼我照著跑 顯示cfit.subsagn ?發生了什麼事 09/13 20:27
2F：→ ksr310135: 不知道呢！ 09/13 22:21