Lorentz2D

class sherpa.astro.models.Lorentz2D(name='lorentz2d')

Bases: sherpa.models.model.ArithmeticModel

Two-dimensional un-normalised Lorentz function.

fwhm

The full-width half maximum.

xpos

The center of the model on the x0 axis.

ypos

The center of the model on the x1 axis.

ellip

The ellipticity of the model.

theta

The angle of the major axis. It is in radians, measured counter-clockwise from the X0 axis (i.e. the line X1=0).

ampl

The amplitude refers to the maximum peak of the model.

See also

Beta1D, DeVaucouleurs2D, HubbleReynolds, Lorentz1D, Sersic2D

Notes

The functional form of the model for points is:

f(x0,x1) = ampl / (1 + 4 * r(x0,x1)^2)

r(x0,x1)^2 = xoff(x0,x1)^2 * (1-ellip)^2 + yoff(x0,x1)^2
             -------------------------------------------
                         fwhm^2 * (1-ellip)^2

xoff(x0,x1) = (x0 - xpos) * cos(theta) + (x1 - ypos) * sin(theta)

yoff(x0,x1) = (x1 - ypos) * cos(theta) - (x0 - xpos) * sin(theta)

and for an integrated grid it is the integral of this over the bin.

Attributes Summary

thawedparhardmaxes
thawedparhardmins
thawedparmaxes
thawedparmins
thawedpars

Methods Summary

apply(outer, \*otherargs, \*\*otherkwargs)
calc(\*args, \*\*kwargs)
get_center()
guess(dep, \*args, \*\*kwargs)
reset()
set_center(xpos, ypos, \*args, \*\*kwargs)
startup()
teardown()

Attributes Documentation

thawedparhardmaxes

thawedparhardmins

thawedparmaxes

thawedparmins

thawedpars

Methods Documentation

apply(outer, *otherargs, **otherkwargs)

calc(*args, **kwargs)

get_center()

guess(dep, *args, **kwargs)

reset()

set_center(xpos, ypos, *args, **kwargs)

startup()

teardown()