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Fit Curves Types

This is the table of predefined Fit Curves.

Name	Formula	Additional Properties
Line
Parabola		Vertex: $x_0 = − b / {2 a}$ $y_0 = c − {b^2} / {4 a}$
Gaussian	$y = a exp(− ln(2) ({x−x_0}/dx)^2)$	Area: Standard deviation:
Gaussian-A (normalized)	$y = sqrt{{ln {2}} / pi} ~ a / dx exp(− ln(2) ({x−x_0}/dx)^2)$	Amplitude: Standard deviation:
Lorentzian	$y = a 1 / {1 + ({x−x_0} / dx)^2}$	Area:
Lorentzian-A (normalized)	$y = a / {pi dx} 1 / {1 + ({x−x_0} / dx)^2}$	Amplitude:
Gauss Derivative	$y = − 2 ln(2) ~ {a (x−x_0)} / {dx^2} exp(− ln(2) ({x−x_0}/dx)^2)$	Area (second integral): Standard deviation: Peak-to-peak horizontal: $p_x = sqrt{2/{ln {2}}} ~ dx$ Peak-to-peak vertical: $p_y = 2 sqrt{{2 ln {2}} / e} ~ a / dx$
Lorentz Derivative	$y=−2 a {x−x_0}/{dx^2} {(1 + ({x−x_0} / dx)^2)^{−2}}$	Area (second integral): Peak-to-peak horizontal: $p_x = 2/{sqrt {3}} ~ dx$ Peak-to-peak vertical: $p_y = {3 sqrt {3}} / 4 ~ a / dx$

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