non linear regression with 3 equations

I have y1=k1(x1), y2=k2(x2), and y3=k3(x3) they are in ODE form I would like to fit my data, (y1,x1), (y2,x2), and (y3,x3) and find k1, k2, and k3? please help!! for non linear fiting, any method would be OK.

Answer 1

[you]

you may try another software named 1stOpt or Auto2Fit, it is easy for ODE fit.

[huazai2020]

What is the difference between 1stOpt or Auto2Fit?

[Walter Roberson]

No difference. Auto2Fit was renamed to 1stOpt . The publisher appears to be 7D-soft