help for gaussian fitting in labview 7.1

[njutcgj]

I am rookie to labview. I try to do the gaussian fitting in labview 7.1. but everytime the fitting curve looks freak. Suggestios & help needed!

Appreciate in advance!

(set slope to 0.02, threshold to -1050, histogram parameter is used to set as -100 for low, -95 for high, 0.005 for step)

[Verne_D]

Hello njutcgj,

It looks like you're using a custom subVI to generate your histogram. Are there resource that guide you through it's implementation? Where did you get this VI, or did you write it? It might be useful to post a screenshot of the graph displaying the freak behavior you describe.

If you would like some guidance on getting more familiar with the LabVIEW environment, a great collecting of learning tools are available here. There are curve fitting VIs built into LabVIEW that more people on these forums will familair with, is there an advantage of this custom subVI?

It might also help to go through the troubleshooting steps you've tried and the results you've encountered. The community will be able to help you in a much more targeted way if we know what your problem solving approach has been thus far. I hope that you'll be able to take full advantage of this resource and we can help steer you towards a solution.

[njutcgj]

Thanks for reply and help!

The subVI for histogram is programmed by ourselves.  It is special for histogrambuilding.

As for fitting, i tried to used different conditions in derivative terminal of nonliear fitting, however both of them don't work well.  One is called 'numerical'; another one is called 'formulated'. That 's all i did till now. I could not figure out what 's wrong with that. Help is greatly needed!