deriv_eta

TRXASprefitpack.mathfun.deriv_eta(fwhm_G: float, fwhm_L: float) → Tuple[float, float]

Calculate gradient of eta of pseudo voigt profile with fwhm_G, fwhm_L based on Journal of Applied Crystallography. 33 (6): 1311–1316.

Parameters:

• fwhm_G – full width at half maximum of gaussian part

• fwhm_L – full width at half maximum of lorenzian part

Returns:

gradient of eta(fwhm_G, fwhm_L)