#pragma rtGlobals=3		// Use modern global access method and strict wave access.

Function/S DoubleSFG_PeakFuncInfo(InfoDesired)
	Variable InfoDesired
	
	String info=""
	
	Switch (InfoDEsired)
		case PeakFuncInfo_ParamNames:
			info = "w;w1;w2;A1;A2;G1;G2" // w = wavenumber or "x", w1 = peak center, A1 = peak's amplitude,  
			break;							//G1 = the peak's phase. 2 refres to the second peak.
		case PeakFuncInfo_PeakFName:
			info = "DoubleSFG_Peak"
			break;
		case PeakFuncInfo_GaussConvFName:
			info = "SimpleLorentzianGuess"
			break;
		case PeakFuncInfo_ParameterFunc:
			info = "DoubleSFG_PeakParams"
			break;
		case PeakFuncInfo_DerivedParamNames:
			info = "Location;Height;Area;FWHM;Wavenumber;Amplitude;Phase"
			break;
		default:
			break;
	endSwitch

	return info
end

Function SimpleLorentzianGuess(w) //Initial guess?
	Wave w
	
	Redimension/N=3 w
	// width of Lorenzian needs to be modified from the estimated Gaussian width
	w[2] = w[1]*w[2]*sqrt(pi)
	return 0
end



Function DoubleSFG_Peak(w, yw, xw, A1, A2, G1, G2, w1, w2) // w = wavenumber or "x", w1 = peak center, A1 = peak's amplitude,  
														           //G1 = the peak's phase.
	Wave w
	Wave yw, xw, A1, A2, G1, G2, w1, w2
	
	Variable/C sqrtJ = cmplx(0,1)
	yw = ((abs(A1/((xw-w1)+G1*sqrtJ) + A2/(x-w2)+G2*sqrtJ)))^2
end

Function DoubleSFG_PeakParams(wW, wA, wP, outWave) //wW=Wavenuber, wA=Amplitude, wP=Phase initial guesses.
	Wave wW, wA, wP, outWave
	
	
	//Location
	outWave[0][0] = wW[0]
	outWave[0][1] = NaN
	
	Variable amp = wA[2]
	
	//Amplitude
	outWave[1][0] = amp
	outWave[1][1] = NaN
	
	//Phase
	outWave[2][0] = wP[2]
	outWave[2][1] = NaN
end