Disk2D

class sherpa.astro.models.Disk2D(name='disk2d')

Bases: sherpa.models.model.RegriddableModel2D

Two-dimensional uniform disk model.

Two-dimensional step function model consisting of a uniform intensity disk.

xpos

The center of the disk on the x0 axis.

ypos

The center of the disk on the x1 axis.

ampl

The amplitude of the signal within the disk.

r0

The radius of the disk.

See also

Shell2D

Notes

The functional form of the model for points is:

f(x0,x1) = ampl  if (x0 - xpos)^2 + (x1 - ypos)^2 <= r0^2

         = 0     otherwise

For grids, the x0lo,x1lo values are used in the above equation.

This model was provided by Christoph Deil.

Attributes Summary

thawedparhardmaxes
thawedparhardmins
thawedparmaxes
thawedparmins
thawedpars

Methods Summary

apply(outer, *otherargs, **otherkwargs)
calc(p, x, y, *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(*args, **kwargs)
startup()	Called before a model may be evaluated multiple times.
teardown()	Called after a model may be evaluated multiple times.

Attributes Documentation

thawedparhardmaxes

thawedparhardmins

thawedparmaxes

thawedparmins

thawedpars

Methods Documentation

apply(outer, *otherargs, **otherkwargs)

calc(p, x, y, *args, **kwargs)

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).

get_center()

guess(dep, *args, **kwargs)

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.

regrid(*arrays)

reset()

set_center(*args, **kwargs)

startup()

Called before a model may be evaluated multiple times.

See also

teardown()

teardown()

Called after a model may be evaluated multiple times.

See also

setup()