Lorentz2D

Function

$z=z_0+\frac A{\left[ 1+\left( \frac{x-x_c}{w_1}\right) ^2\right] \left[ 1+\left( \frac{y-y_c}{w_2}\right) ^2\right] }$

Non-linear Sigmoid (Logistic Cumulative) Function

Number: 6

Name:	Meanings:	Lower Bounds:
$z_0$	z offset
A	height
$x_c$	x center
$w_1$	x width	$w_1>0$
$y_c$	y center
$w_2$	y width	$w_2>0$

$FWHM_x=2w_1$

$FWHM_y=2w_2$

$Volume=Aw_1w_2\pi^2$

fitfunc\Lorentz2D.fdf