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oscilloscope, curve fitting , and other problems

I am working on a project for senior conference in chemistry. It involves thermal lensing, which is where a laser is passed through a colored solution. Blue solution absorbs at the wavelength of the laser and heats up. This causes the laser to be broadend and it is deflected from the detector. I have used labview and the ni elvis oscilloscope to display the data in a VI. The data appears as a series of exponential decays, because the chopper hits the laser and it causes the solution to cool down.
I have taken the natural log of the data and siplayed it in another graph. This makes the data from the exponential decay linear. Now, I want to take a section of this data, from y to y+n, and apply a linear fit and display it while it is collected. I also want to be able to take the slope of this line.
If anyone can explain how to do this I would greatly appreciate it. Also, if anyone has any information on where to find some oscilloscope VIs other than those from the NI example finder, that would be great to. Thank you for reading this, and feel free to offer any feedback.
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Hello,

The array subset function will allow you to extract a subset of your data array.

I'm not sure what version of LabVIEW you are using, but if it's 8.x then there are fitting functions you can use in the Mathematics -> Fitting palette.  There are also functions in 7.x for this.

Together those functions should allow you to fit a function to a subset of your data.

For additional examples or drivers for devices, you should search ni.com, the developer zone, and/or more specifically the instrument driver resources.

Best Regards,

JLS

Best,
JLS
Sixclear
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