Invert a function

Function /wave Invert(w[,lo,hi,points])
	Wave w
	Variable lo,hi,points
#if exists("Interpolate2")
	WaveStats /Q w
	lo=ParamIsDefault(lo) ? V_min : lo
	hi=ParamIsDefault(hi) ? V_max : hi
	points=ParamIsDefault(points) ? 1000 : points
	String invert_name=CleanUpName(NameOfWave(w)+"_Inv",1)
	Make /o/n=(points) $invert_name /wave=Inverted=0
	SetScale /I x,lo,hi,Inverted
	Duplicate /free w Temp
	Temp=DimOffset(w,0)+p*DimDelta(w,0)
	Interpolate2 /T=1 /I=3 /Y=Inverted w,Temp
	return Inverted
#else
	printf "Need Interpolate XOP.\r"
#endif
End