Origin Version (Origin Pro 7.5 SRO): Operating System:(Windows 2000 SP4)
Hallo. I am newbie with Origin and i am facing a problem with advanced fitting tool. I want to find the fitting curve according to the equation y=100-a(1-1/e^bt) for the following data:
I have customized the equation (as y script)The problem is that i dont know the initial a and b values in order to make the parameters initialization. So when i try t make the fit (without giving any a and b value and with automatic parameter initialization enabled) I receive the answer: "Error. The parameters a and b are not properly initialized. Check their values"
I would appreciate if you could me with this problem Nikos
A set of initial values for all of the parameters is of course required for the iterative process to begin. With built-in functions we provide code that examines the data and comes up with initial guess values. You are working with a user-defined function, so you have two choices: 1> write some parameter initialization code, similar to what we do, to come up with values - this is beneficial if you wish to fit many datasets with this equation 2> put in some constant values - note that you can save the constant values in the fdf and if the values are "reasonable" the iterative process will converge
Problem with advanced fiiting tool
Posted - 02/01/2008 : 05:36:37 AM
