Ring2D

class astropy.modeling.functional_models.Ring2D(amplitude=1, x_0=0, y_0=0, r_in=1, width=1, r_out=None, **kwargs)[source]

Bases: astropy.modeling.Fittable2DModel

Two dimensional radial symmetric Ring model.

Parameters
amplitudefloat

Value of the disk function

x_0float

x position center of the disk

y_0float

y position center of the disk

r_infloat

Inner radius of the ring

widthfloat

Width of the ring.

r_outfloat

Outer Radius of the ring. Can be specified instead of width.

Notes

Model formula:

\[\begin{split}f(r) = \left \{ \begin{array}{ll} A & : r_{in} \leq r \leq r_{out} \\ 0 & : \text{else} \end{array} \right.\end{split}\]

Where \(r_{out} = r_{in} + r_{width}\).

Attributes Summary

amplitude

input_units

This property is used to indicate what units or sets of units the evaluate method expects, and returns a dictionary mapping inputs to units (or None if any units are accepted).

param_names

r_in

width

x_0

y_0

Methods Summary

evaluate(x, y, amplitude, x_0, y_0, r_in, width)

Two dimensional Ring model function.

Attributes Documentation

amplitude = Parameter('amplitude', value=1.0)
input_units
param_names = ('amplitude', 'x_0', 'y_0', 'r_in', 'width')
r_in = Parameter('r_in', value=1.0)
width = Parameter('width', value=1.0)
x_0 = Parameter('x_0', value=0.0)
y_0 = Parameter('y_0', value=0.0)

Methods Documentation

static evaluate(x, y, amplitude, x_0, y_0, r_in, width)[source]

Two dimensional Ring model function.