Nonlinear Curve Fit and using static data

I am trying to fit data to a 2D function using the Nonlinear Curve Fit VI in Labview 8.2.1, but I would like to also include 2 parameters that I don't want to be optimized. I cannot directly use constants since every time I run the fitting I need to change the 2 parameter values. I tried to modify the example by Altenbach according to my own application in the link below.
http://forums.ni.com/ni/board/message?board.id=170&message.id=230831
I think the problem is that I don't completely understand how to use the static VI reference with the Nonlinear Curve Fit VI? It looks like there is a static data control that I could use to add additional parameters, but I am not sure? I can get Altenbach's code to work if I change the function to something different, and even if I change the number of inital fitted parameters. I just can't figure out how I can add parameters using a control that will not be optimized. I can attach an example, but it is very similar to Altenbach's code except the function is different, and I am trying to add additional parameters that are not optimized. Thanks for any help.
Kevin Baker

Thanks Trey. I am sorry I didn't make it clear what I was talking about before. I am attaching an example that will hopefully clarify what I would like to do. When I try to pass the static reference to the Nonlinear Fit VI it says gives me a broken wire and says "function conflict". I am assuming the problem is that I inserted another control to the VI when I wasn't supposed to. I just don't know of any other way to pass data into the VI, and still have the Nonlinear Fit VI still work? What is the "data" control in the Nonlinear Fit VI used for anyway? It seems that that it was want I need, but I don't know how to use it? Thanks again for any help.
Attachments:
Fit equation.vi ‏15 KB
general lorentzian.vi ‏26 KB

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That looks like a plot of the input data.
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jcyth wrote:
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帖子被trinight在02-11-2006 07:51 PM时编辑过了
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Nonlinear Curve Fit and using static data

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