lsst.pipe.tasks.functors.Photometry Class Reference

Inheritance diagram for lsst.pipe.tasks.functors.Photometry:

Public Member Functions
	__init__ (self, colFlux, colFluxErr=None, **kwargs)
	columns (self)
	name (self)
	hypot (cls, a, b)
	dn2flux (self, dn, fluxMag0)
	dn2mag (self, dn, fluxMag0)
	dn2fluxErr (self, dn, dnErr, fluxMag0, fluxMag0Err)
	dn2MagErr (self, dn, dnErr, fluxMag0, fluxMag0Err)

Public Attributes
	vhypot
	col
	colFluxErr
	fluxMag0
	fluxMag0Err

Static Public Attributes
tuple	AB_FLUX_SCALE = (0 * u.ABmag).to_value(u.nJy)
float	LOG_AB_FLUX_SCALE = 12.56
float	FIVE_OVER_2LOG10 = 1.085736204758129569
int	COADD_ZP = 27

Detailed Description

Base class for Object table calibrated fluxes and magnitudes.

Definition at line 1562 of file functors.py.

Constructor & Destructor Documentation

__init__()

lsst.pipe.tasks.functors.Photometry.__init__	(		self,
			colFlux,
			colFluxErr = None,
		**	kwargs )

Reimplemented from lsst.pipe.tasks.functors.Functor.

Definition at line 1571 of file functors.py.

    def __init__(self, colFlux, colFluxErr=None, **kwargs):
        self.vhypot = np.vectorize(self.hypot)
        self.col = colFlux
        self.colFluxErr = colFluxErr
 
        self.fluxMag0 = 1./np.power(10, -0.4*self.COADD_ZP)
        self.fluxMag0Err = 0.
 
        super().__init__(**kwargs)
 

Member Function Documentation

columns()

lsst.pipe.tasks.functors.Photometry.columns

(

self

)

Columns required to perform calculation.

Reimplemented from lsst.pipe.tasks.functors.Functor.

Reimplemented in lsst.pipe.tasks.functors.NanoJanskyErr.

Definition at line 1582 of file functors.py.

    def columns(self):
        return [self.col]
 

dn2flux()

lsst.pipe.tasks.functors.Photometry.dn2flux	(		self,
			dn,
			fluxMag0 )

Convert instrumental flux to nanojanskys.

Definition at line 1599 of file functors.py.

    def dn2flux(self, dn, fluxMag0):
        """Convert instrumental flux to nanojanskys."""
        return self.AB_FLUX_SCALE * dn / fluxMag0
 

dn2fluxErr()

lsst.pipe.tasks.functors.Photometry.dn2fluxErr	(		self,
			dn,
			dnErr,
			fluxMag0,
			fluxMag0Err )

Convert instrumental flux error to nanojanskys.

Definition at line 1610 of file functors.py.

    def dn2fluxErr(self, dn, dnErr, fluxMag0, fluxMag0Err):
        """Convert instrumental flux error to nanojanskys."""
        retVal = self.vhypot(dn * fluxMag0Err, dnErr * fluxMag0)
        retVal *= self.AB_FLUX_SCALE / fluxMag0 / fluxMag0
        return retVal
 

dn2mag()

lsst.pipe.tasks.functors.Photometry.dn2mag	(		self,
			dn,
			fluxMag0 )

Convert instrumental flux to AB magnitude.

Definition at line 1603 of file functors.py.

    def dn2mag(self, dn, fluxMag0):
        """Convert instrumental flux to AB magnitude."""
        with warnings.catch_warnings():
            warnings.filterwarnings('ignore', r'invalid value encountered')
            warnings.filterwarnings('ignore', r'divide by zero')
            return -2.5 * np.log10(dn/fluxMag0)
 

dn2MagErr()

lsst.pipe.tasks.functors.Photometry.dn2MagErr	(		self,
			dn,
			dnErr,
			fluxMag0,
			fluxMag0Err )

Convert instrumental flux error to AB magnitude error.

Definition at line 1616 of file functors.py.

    def dn2MagErr(self, dn, dnErr, fluxMag0, fluxMag0Err):
        """Convert instrumental flux error to AB magnitude error."""
        retVal = self.dn2fluxErr(dn, dnErr, fluxMag0, fluxMag0Err) / self.dn2flux(dn, fluxMag0)
        return self.FIVE_OVER_2LOG10 * retVal
 
 

hypot()

lsst.pipe.tasks.functors.Photometry.hypot	(		cls,
			a,
			b )

Compute sqrt(a^2 + b^2) without under/overflow.

Definition at line 1590 of file functors.py.

    def hypot(cls, a, b):
        """Compute sqrt(a^2 + b^2) without under/overflow."""
        if np.abs(a) < np.abs(b):
            a, b = b, a
        if a == 0.:
            return 0.
        q = b/a
        return np.abs(a) * np.sqrt(1. + q*q)
 

name()

lsst.pipe.tasks.functors.Photometry.name

(

self

)

Reimplemented from lsst.pipe.tasks.functors.Functor.

Definition at line 1586 of file functors.py.

    def name(self):
        return f'mag_{self.col}'
 

Member Data Documentation

AB_FLUX_SCALE

tuple lsst.pipe.tasks.functors.Photometry.AB_FLUX_SCALE = (0 * u.ABmag).to_value(u.nJy)

static

Definition at line 1565 of file functors.py.

COADD_ZP

int lsst.pipe.tasks.functors.Photometry.COADD_ZP = 27

static

Definition at line 1569 of file functors.py.

col

lsst.pipe.tasks.functors.Photometry.col

Definition at line 1573 of file functors.py.

colFluxErr

lsst.pipe.tasks.functors.Photometry.colFluxErr

Definition at line 1574 of file functors.py.

FIVE_OVER_2LOG10

float lsst.pipe.tasks.functors.Photometry.FIVE_OVER_2LOG10 = 1.085736204758129569

static

Definition at line 1567 of file functors.py.

fluxMag0

lsst.pipe.tasks.functors.Photometry.fluxMag0

Definition at line 1576 of file functors.py.

fluxMag0Err

lsst.pipe.tasks.functors.Photometry.fluxMag0Err

Definition at line 1577 of file functors.py.

LOG_AB_FLUX_SCALE

float lsst.pipe.tasks.functors.Photometry.LOG_AB_FLUX_SCALE = 12.56

static

Definition at line 1566 of file functors.py.

vhypot

lsst.pipe.tasks.functors.Photometry.vhypot

Definition at line 1572 of file functors.py.

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/pipe_tasks/g8ffcb69f3d+0065d7bbc8/python/lsst/pipe/tasks/functors.py