lsst.pipe.tasks.colorterms.Colorterm Class Reference

Colorterm correction for one pair of filters. More...

Inheritance diagram for lsst.pipe.tasks.colorterms.Colorterm:

Public Member Functions
def	transformSource (self, source)
	Transform the brightness of a source. More...
def	transformMags (self, primary, secondary)
	Transform brightness. More...
def	propagateFluxErrors (self, primaryFluxErr, secondaryFluxErr)

Static Public Attributes
	primary = Field(dtype=str, doc="name of primary filter")
	secondary = Field(dtype=str, doc="name of secondary filter")
	c0 = Field(dtype=float, default=0.0, doc="Constant parameter")
	c1 = Field(dtype=float, default=0.0, doc="First-order parameter")
	c2 = Field(dtype=float, default=0.0, doc="Second-order parameter")

Detailed Description

Colorterm correction for one pair of filters.

The transformed magnitude p' is given by p' = primary + c0 + c1*(primary - secondary) + c2*(primary - secondary)**2

To construct a Colorterm, use keyword arguments: Colorterm(primary=primaryFilterName, secondary=secondaryFilterName, c0=c0value, c1=c1Coeff, c2=c2Coeff) where c0-c2 are optional. For example (omitting c2): Colorterm(primary="g", secondary="r", c0=-0.00816446, c1=-0.08366937)

This is subclass of Config. That is a bit of a hack to make it easy to store the data in an appropriate obs_* package as a config override file. In the long term some other means of persistence will be used, at which point the constructor can be simplified to not require keyword arguments. (Fixing DM-2831 will also allow making a custom constructor).

Definition at line 39 of file colorterms.py.

Member Function Documentation

propagateFluxErrors()

def lsst.pipe.tasks.colorterms.Colorterm.propagateFluxErrors	(		self,
			primaryFluxErr,
			secondaryFluxErr
	)

Definition at line 80 of file colorterms.py.

transformMags()

def lsst.pipe.tasks.colorterms.Colorterm.transformMags	(		self,
			primary,
			secondary
	)

Transform brightness.

Parameters

[in]	primary	brightness in primary filter (magnitude)
[in]	secondary	brightness in secondary filter (magnitude)

Returns

the transformed brightness (as a magnitude)

Definition at line 70 of file colorterms.py.

transformSource()

def lsst.pipe.tasks.colorterms.Colorterm.transformSource	(		self,
			source
	)

Transform the brightness of a source.

Parameters

[in]

source

source whose brightness is to be converted; must support get(filterName) (e.g. source.get("r")) method, as do afw::table::Source and dicts.

Returns

the transformed source magnitude

Definition at line 61 of file colorterms.py.

Member Data Documentation

c0

lsst.pipe.tasks.colorterms.Colorterm.c0 = Field(dtype=float, default=0.0, doc="Constant parameter")

static

Definition at line 57 of file colorterms.py.

c1

lsst.pipe.tasks.colorterms.Colorterm.c1 = Field(dtype=float, default=0.0, doc="First-order parameter")

static

Definition at line 58 of file colorterms.py.

c2

lsst.pipe.tasks.colorterms.Colorterm.c2 = Field(dtype=float, default=0.0, doc="Second-order parameter")

static

Definition at line 59 of file colorterms.py.

primary

lsst.pipe.tasks.colorterms.Colorterm.primary = Field(dtype=str, doc="name of primary filter")

static

Definition at line 55 of file colorterms.py.

secondary

lsst.pipe.tasks.colorterms.Colorterm.secondary = Field(dtype=str, doc="name of secondary filter")

static

Definition at line 56 of file colorterms.py.

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The documentation for this class was generated from the following file:

• python/lsst/pipe/tasks/colorterms.py