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Paulie Walnuts
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Need urgent help with Analysis.Math to calculate slope

Hi all!

I am trying to use NationalInstruments.Analysis.Math to calculate the slope and intercept of a graph using VB. I'm using the CurveFit property but cannot find any resources regarding the applicable syntax. Any any help would be greatly appreciated.

 

Thanks in advance!

Member
Oli.P
Posts: 122
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Re: Need urgent help with Analysis.Math to calculate slope

Hi Paulie,

 

Have you had a look at the Getting Started guides for Measurement Studio?  There are versiosn for Visual Studio 2010, and Visual Studio 2005 and 2008.

 

This might also be useful.

 

I hope that helps.

 

Kind Regards,

Oli
LabVIEW Student Ambassador
National Instruments UK
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D_Biel
Posts: 676
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Re: Need urgent help with Analysis.Math to calculate slope

Maybe you want something like this?

 

            Dim xArray() As Double = New Double(samples - 1) {}
            Dim dataArray() As Double = New Double(samples - 1) {}
            Dim fittedArray() As Double = New Double(samples - 1) {}
            Dim slope As Double
            Dim intercept As Double
            Dim residue As Double

            fittedArray = CurveFit.LinearFit(xArray, dataArray, FitMethod.LeastSquare, slope, intercept, residue)

 The LinearFit method has several overloaded methods, but the simplest one that still provides the slope and intercept output is:

 

Public Shared Function LinearFit ( _
	inputXData As Double(), _
	inputYData As Double(), _
	fitMethod As FitMethod, _
	<OutAttribute> ByRef slope As Double, _
	<OutAttribute> ByRef intercept As Double, _
	<OutAttribute> ByRef residue As Double _
) As Double()

 

National Instruments
Product Support Engineer