2.1.11.3 nlfFit

1 Description
2 Syntax
3 Parameters
4 Return
5 Examples
6 Remark
7 See Also
8 Header to Include
9 Reference

Description

Get the value of the specified dependent variable for the specified value of the independent variable.

Syntax

double nlfFit( double dx, int nDepend = 0 )

Parameters

dx: [input] value of the independent variable
nDepend: [input] dependent variable ( 0 based offset)

Return

Returns the value of the specified dependent variable for the given value of the independent variable.

Examples

EX1

bool LTNLSF_fit(curvebase& crvData, vector& fitx, vector& fity, int i1, int i2, LPCSTR lpcszFunc)
{
    int nMissing, nSrcOffset;
    Curve cvcpy(crvData, nMissing, nSrcOffset, CURVECOPY_SKIP_MISSING_INSIDE, i1, i2);
    
    using NLSF = LabTalk.NLSF;
    NLSF.Init();                    // initialize fitter
    
    NLSF.Func$ = lpcszFunc;
    NLSF.Output(0);
    NLSF.FitData$ = cvcpy.GetName();  
    NLSF.Execute("parainit");        // perform auto parameter initialization
    NLSF.Iterate(100);
    NLSF.End(13);
    
    Dataset cvcpyx;
    cvcpy.AttachX(cvcpyx);
    fitx = cvcpyx;
    fity = nlfFit(fitx); // get fit Y values given X values, using Origin C vector mechanism with functions with double argument
    return true;
}

void test(int i1 = 0, int i2 = -1, string strFunc = "Gauss", string strRwks = "FitCurve")
{
    Worksheet wksData = Project.ActiveLayer();
    Curve crvData(wksData, 0, 1);
    if(!crvData)
        return;
    
    vector vx, vy;    
    LTNLSF_fit(crvData, vx, vy, i1, i2, strFunc);
    
    Worksheet wksResult(strRwks);
    if(!wksResult)
    {
        wksResult.Create();
        wksResult.GetPage().Rename(strRwks);
    }
    Dataset fitdx(wksResult, 0);
    Dataset fitdy(wksResult, 1);
    fitdx = vx;
    fitdy = vy;
}

Remark

Get the value of the specified dependent variable for the specified value of the independent variable. This function is used in conjunction with the internal Origin Non-linear Least Squares Fitter (NLSF) object and uses the most recent fitting function and parameter values specified through the NLSF interface or through script.