4楼: Originally posted by dingd at 2012-11-30 16:51:41
估计是你的初值选的不好吧，1stOpt不用猜初值，拟合比Origin强大方便的多：

Function y=(x/(h-x))+(k1*x/(1+k1*x))*(1-(4*k1*k2*x-2*(1+k1*x)*(k1*k2*x)^(1/2))/(4*k1*k2*x-(1+k1*x)^2))+(2*k1*k2*x-(1+k1*x)*(k ...

2楼: Originally posted by dingd at 2012-11-30 16:12:12
最好把数据和公式以文本格式一起放上来。

Function y=(x/(h-x))+(k1*x/(1+k1*x))*(1-(4*k1*k2*x-2*(1+k1*x)*(k1*k2*x)^(1/2))/(4*k1*k2*x-(1+k1*x)^2))+(2*k1*k2*x-(1+k1*x)*(k1*k2*x)^(1/2))/(4*k1*k2*x-(1+k1*x)^2);
Data;
//x        y
0.01        0.02121
0.02        0.02971
0.05        0.03939
0.09        0.05438
0.26        0.07518
0.43        0.08643
0.59        0.09555
0.81        0.1079
0.98        0.1158
1.49        0.13528
2.16        0.1572
2.55        0.16813
3.08        0.18184
4.53        0.21938
6.01        0.2593
7.05        0.28667
8.08        0.31317
9.22        0.34592