DeVaucouleurs2D¶
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class
sherpa.astro.models.
DeVaucouleurs2D
(name='devaucouleurs2d')[source] [edit on github]¶ Bases:
sherpa.models.model.RegriddableModel2D
Two-dimensional de Vaucouleurs model.
A spatial de Vaucouleurs profile which is a formulation of the R^(1/4) law introduced by [1]. It is a special case of the
Sersic2D
model withn=4
, as described in [2], [3], and [4].-
r0
¶ The core radius.
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xpos
¶ The center of the model on the x0 axis.
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ypos
¶ The center of the model on the x1 axis.
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ellip
¶ The ellipticity of the model.
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theta
¶ The angle of the major axis. It is in radians, measured counter-clockwise from the X0 axis (i.e. the line X1=0).
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ampl
¶ The amplitude refers to the maximum peak of the model.
See also
Notes
The model used is the same as the
Sersic2D
model withn=4
.References
[1] de Vaucouleurs G., 1948, Ann. d’Astroph. 11, 247 http://adsabs.harvard.edu/abs/1948AnAp…11..247D [2] http://ned.ipac.caltech.edu/level5/March05/Graham/Graham2.html [3] Graham, A. & Driver, S., 2005, PASA, 22, 118 http://adsabs.harvard.edu/abs/2005PASA…22..118G [4] Ciotti, L. & Bertin, G., A&A, 1999, 352, 447-451 http://adsabs.harvard.edu/abs/1999A%26A…352..447C Attributes Summary
thawedparhardmaxes
thawedparhardmins
thawedparmaxes
thawedparmins
thawedpars
Methods Summary
apply
(outer, *otherargs, **otherkwargs)calc
(*args, **kwargs)Evaluate the model on a grid. get_center
()guess
(dep, *args, **kwargs)Set an initial guess for the parameter values. regrid
(*arrays)reset
()set_center
(xpos, ypos, *args, **kwargs)startup
(cache)Called before a model may be evaluated multiple times. teardown
()Called after a model may be evaluated multiple times. Attributes Documentation
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thawedparhardmaxes
¶
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thawedparhardmins
¶
-
thawedparmaxes
¶
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thawedparmins
¶
-
thawedpars
¶
Methods Documentation
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apply
(outer, *otherargs, **otherkwargs) [edit on github]¶
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calc
(*args, **kwargs)[source] [edit on github]¶ Evaluate the model on a grid.
Parameters: - p (sequence of numbers) – The parameter values to use. The order matches the
pars
field. - *args – The model grid. The values can be scalar or arrays, and the number depends on the dimensionality of the model and whether it is being evaluated over an integrated grid or at a point (or points).
- p (sequence of numbers) – The parameter values to use. The order matches the
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get_center
()[source] [edit on github]¶
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guess
(dep, *args, **kwargs)[source] [edit on github]¶ Set an initial guess for the parameter values.
Attempt to set the parameter values, and ranges, for the model to match the data values. This is intended as a rough guess, so it is expected that the model is only evaluated a small number of times, if at all.
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regrid
(*arrays) [edit on github]¶
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reset
() [edit on github]¶
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set_center
(xpos, ypos, *args, **kwargs)[source] [edit on github]¶
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startup
(cache) [edit on github]¶ Called before a model may be evaluated multiple times.
See also
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teardown
() [edit on github]¶ Called after a model may be evaluated multiple times.
See also
setup()
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