• Function Name: FitConv


• Function Type: User-Defined


• Independent Variables: x


• Dependent Variables: y


• Parameter Names: y0, A1, A2, t1, t2


• Function Form: Origin C

Function:

#pragma warning(error : 15618)
#include <origin.h>
// Header files need to be included
#include <ONLSF.H>
#include <fft_utils.h>
//
// 
void _nlsfTestConv(
// Fit Parameter(s):
double y0, double A1, double A2, double t1, double t2,
// Independent Variable(s):
double x,
// Dependent Variable(s):
double& y)
{
	// Beginning of editable part	
	NLFitContext *pCtxt = Project.GetNLFitContext();
        Worksheet wks;
        DataRange dr;
        int c1,c2;
        dr = pCtxt->GetSourceDataRange(); //Get the source data range
        dr.GetRange(wks, c1, c2);  //Get the source data worksheet
	if ( pCtxt )
	{	
		// Vector for the output signal in each iteration.
		static vector vSignal;
		// If parameters were updated, we will recalculate the convolution result.
		BOOL bIsNewParamValues = pCtxt->IsNewParamValues();
		if ( bIsNewParamValues )
		{
			// Read sampling and response data from worksheet.
			Dataset dsSampling(wks, 0);
			Dataset dsResponse(wks, 2);
			int iSize = dsSampling.GetSize();
 
			vector vResponse, vSample;
 
			vResponse = dsResponse;
			vSample = dsSampling;
 
			vSignal.SetSize(iSize);
			vResponse.SetSize(iSize);
			vSample.SetSize(iSize);
 
			// Compute the exponential decay curve
			vSignal = A1 * exp( -t1*vSample ) + A2 * exp( -t2*vSample );
			// Perform convolution
			int iRet = fft_fft_convolution(iSize, vSignal, vResponse);
                        //Correct the convolution by multiplying the sampling interval
                        vSignal = (vSample[1]-vSample[0])*vSignal;
 
 
		}
 
		NLSFCURRINFO    stCurrInfo;
		pCtxt->GetFitCurrInfo(&stCurrInfo);
		// Get the data index for the iteration
		int nCurrentIndex = stCurrInfo.nCurrDataIndex;
		// Get the evaluated y value
		y = vSignal[nCurrentIndex] + y0;
		// For compile the function, since we haven't use x here.
		x;
	}
	// End of editable part
}