[求助] 已知函数形式，如何拟合其中的多个系数。

Variable y,t;
Function  y=r1-r1*exp(-t/s1)+r2-r2*exp(-t/s2)+r3-r3*exp(-t/s3)+r4-r4*exp(-t/s4);
Data;
0.24  0.003691
0.32 0.004835
0.4 0.005633
0.48 0.006191
0.56 0.006582
0.64 0.006857
0.72 0.007051
0.8 0.007282
0.88 0.007287
0.96 0.00735
1.04 0.007397
1.12 0.00743
1.2 0.007454
1.28 0.007471

3楼: Originally posted by dingd at 2012-06-05 10:05:41
拟合问题推荐用1stOpt：

Variable y,t;
Function  y=r1-r1*exp(-t/s1)+r2-r2*exp(-t/s2)+r3-r3*exp(-t/s3)+r4-r4*exp(-t/s4);
Data;
0.24  0.003691
0.32 0.004835
0.4 0.005633
0.48 0.006191
0.56 0.00 ...