Classes
class	ComputeGraphModel

class	ConstantModel

class	ConstantParameter

class	CoordinateModelBase

class	DependentParameter

class	DeVaucouleursModel

class	ExponentialModel

class	FluxParameterType

class	FreeParameter

class	ModelBase

class	ModelFitting

class	ParameterBase

class	PointSourceModel

class	Prior

class	Range

class	RangeType

class	SersicModel

class	SersicModelBase

class	Unbounded

class	WorldCoordinate

Functions
	get_pos_parameters ()

	get_flux_parameter (type=FluxParameterType.ISO, scale=1)

	pixel_to_world_coordinate (x, y)

	get_sky_coord (x, y)

	radius_to_wc_angle (x, y, rad)

	get_separation_angle (x1, y1, x2, y2)

	get_position_angle (x1, y1, x2, y2)

	get_world_position_parameters (x, y)

	get_world_parameters (x, y, radius, angle, ratio)

	print_model_fitting_info (group, show_params=False, prefix='', file=sys.stderr)

Function Documentation

◆ get_flux_parameter()

sourcextractor.config.model_fitting.get_flux_parameter	(		type = FluxParameterType.ISO,
			scale = 1 )

Convenience function for the flux parameter.

Parameters
----------
type : int
    One of the values defined in FluxParameterType
scale : float
    Scaling of the initial flux. Defaults to 1.

Returns
-------
flux : FreeParameter
    Flux parameter, starting at the flux defined by `type`, and limited to +/- 1e3 times the initial value.

Definition at line 374 of file model_fitting.py.

◆ get_pos_parameters()

sourcextractor.config.model_fitting.get_pos_parameters ( )

Convenience function for the position parameter X and Y.

Returns
-------
x : FreeParameter
    X coordinate, starting at the X coordinate of the centroid and linearly limited to X +/- the object radius.
y : FreeParameter
    Y coordinate, starting at the Y coordinate of the centroid and linearly limited to Y +/- the object radius.
Notes
-----
X and Y are fitted on the detection image X and Y coordinates. Internally, these are translated to measurement
images using the WCS headers.

Definition at line 344 of file model_fitting.py.

◆ get_position_angle()

sourcextractor.config.model_fitting.get_position_angle	(	x1,
		y1,
		x2,
		y2 )

Get the position angle in sky coordinates for two points defined in pixels on the detection image.

Parameters
----------
x1
y1
x2
y2

Returns
-------
Position angle in degrees, normalized to -/+ 90

Definition at line 899 of file model_fitting.py.

References sourcextractor.config.model_fitting.get_sky_coord().

Here is the call graph for this function:

◆ get_separation_angle()

sourcextractor.config.model_fitting.get_separation_angle	(	x1,
		y1,
		x2,
		y2 )

Get the separation angle in sky coordinates for two points defined in pixels on the detection image.

Parameters
----------
x1 : float
y1 : float
x2 : float
y2 : float

Returns
-------
Separation in degrees

Definition at line 879 of file model_fitting.py.

References sourcextractor.config.model_fitting.get_sky_coord().

Here is the call graph for this function:

◆ get_sky_coord()

sourcextractor.config.model_fitting.get_sky_coord	(		x,
			y )

Transform an (X, Y) in pixel coordinates on the detection image to astropy SkyCoord.

Parameters
----------
x : float
y : float

Returns
-------
SkyCoord

Definition at line 844 of file model_fitting.py.

Referenced by sourcextractor.config.model_fitting.get_position_angle(), and sourcextractor.config.model_fitting.get_separation_angle().

◆ get_world_parameters()

sourcextractor.config.model_fitting.get_world_parameters	(	x,
		y,
		radius,
		angle,
		ratio )

Convenience function for generating five dependent parameters, in world coordinates, for the position
and shape of a model.

Parameters
----------
x : ParameterBase
y : ParameterBase
radius : ParameterBase
angle : ParameterBase
ratio : ParameterBase

Returns
-------
ra : DependentParameter
    Right ascension
dec : DependentParameter
    Declination
rad : DependentParameter
    Radius as degrees
angle : DependentParameter
    Angle in degrees
ratio : DependentParameter
    Aspect ratio. It has to be recomputed as the axis of the ellipse may have different ratios
    in image coordinates than in world coordinates

Examples
--------
>>> flux = get_flux_parameter()
>>> x, y = get_pos_parameters()
>>> radius = FreeParameter(lambda o: o.radius, Range(lambda v, o: (.01 * v, 100 * v), RangeType.EXPONENTIAL))
>>> angle = FreeParameter(lambda o: o.angle, Range((-np.pi, np.pi), RangeType.LINEAR))
>>> ratio = FreeParameter(1, Range((0, 10), RangeType.LINEAR))
>>> add_model(group, ExponentialModel(x, y, flux, radius, ratio, angle))
>>> ra, dec, wc_rad, wc_angle, wc_ratio = get_world_parameters(x, y, radius, angle, ratio)
>>> add_output_column('mf_world_angle', wc_angle)

Definition at line 953 of file model_fitting.py.

◆ get_world_position_parameters()

sourcextractor.config.model_fitting.get_world_position_parameters	(		x,
			y )

Convenience function for generating two dependent parameter with world (alpha, delta) coordinates
from image (X, Y) coordinates.

Parameters
----------
x : ParameterBase
y : ParameterBase

Returns
-------
ra : DependentParameter
dec : DependentParameter

See Also
--------
get_pos_parameters

Examples
--------
>>> x, y = get_pos_parameters()
>>> ra, dec = get_world_position_parameters(x, y)
>>> add_output_column('mf_ra', ra)
>>> add_output_column('mf_dec', dec)

Definition at line 922 of file model_fitting.py.

◆ pixel_to_world_coordinate()

sourcextractor.config.model_fitting.pixel_to_world_coordinate	(		x,
			y )

Transform an (X, Y) in pixel coordinates on the detection image to (RA, DEC) in world coordinates.
Parameters
----------
x : float
y : float

Returns
-------
WorldCoordinate

Definition at line 826 of file model_fitting.py.

◆ print_model_fitting_info()

sourcextractor.config.model_fitting.print_model_fitting_info	(	group,
		show_params = False,
		prefix = '',
		file = sys.stderr )

Print a human-readable representation of the configured models.

Parameters
----------
group : MeasurementGroup
    Print the models for this group.
show_params : bool
    If True, print also the parameters that belong to the model
prefix : str
    Prefix each line with this string. Used internally for indentation.
file : file object
    Where to print the representation. Defaults to sys.stderr

Definition at line 1222 of file model_fitting.py.

◆ radius_to_wc_angle()

sourcextractor.config.model_fitting.radius_to_wc_angle	(	x,
		y,
		rad )

Transform a radius in pixels on the detection image to a radius in sky coordinates.

Parameters
----------
x : float
y : float
rad : float

Returns
-------
Radius in degrees

Definition at line 862 of file model_fitting.py.

Classes

Functions