lsst::jointcal::ProperMotion Class Reference

Proper motion data for a reference star or fitted star. More...

#include <ProperMotion.h>

Public Member Functions
	ProperMotion (double ra, double dec, double raErr, double decErr, double raDecCov=0)
	ProperMotion (ProperMotion const &)=default
	ProperMotion (ProperMotion &&)=default
ProperMotion &	operator= (ProperMotion const &)=default
ProperMotion &	operator= (ProperMotion &&)=default
	~ProperMotion ()=default
Point	apply (const Point &star, double timeDeltaYears) const
	Apply proper motion correction to the input star, returning a star with PM-corrected coordinates.

Friends
std::ostream &	operator<< (std::ostream &stream, ProperMotion const &pm)

Detailed Description

Proper motion data for a reference star or fitted star.

Whether to just use these values or fit them is determined by the RefStar and FittedStar they belong to.

Units are radians/year Note: RA proper motion is pm_ra*cos(dec)

Definition at line 45 of file ProperMotion.h.

Constructor & Destructor Documentation

ProperMotion() [1/3]

lsst::jointcal::ProperMotion::ProperMotion ( double ra, double dec, double raErr, double decErr, double raDecCov = 0 )

inline

Definition at line 47 of file ProperMotion.h.

            : _ra(ra), _dec(dec), _raErr(raErr), _decErr(decErr), _raDecCov(raDecCov) {
        _offsetBearing = atan2(dec, ra);
    };

ProperMotion() [2/3]

lsst::jointcal::ProperMotion::ProperMotion ( ProperMotion const & )

default

ProperMotion() [3/3]

lsst::jointcal::ProperMotion::ProperMotion ( ProperMotion && )

default

~ProperMotion()

lsst::jointcal::ProperMotion::~ProperMotion ( )

default

Member Function Documentation

apply()

Point lsst::jointcal::ProperMotion::apply	(	const Point &	star,
		double	timeDeltaYears ) const

Apply proper motion correction to the input star, returning a star with PM-corrected coordinates.

NOTE: This method does not apply to the coordinate errors (Point does not include uncertainty).

Parameters

star	The star to correct for this proper motion.
timeDeltaYears	The difference in time from the correction epoch to correct for, in years.

Returns

The star with corrected coordinates.

Definition at line 34 of file ProperMotion.cc.

                                                                        {
    geom::SpherePoint spherePoint(star.x, star.y, geom::degrees);
    double amount = std::hypot(_ra * timeDeltaYears, _dec * timeDeltaYears);
    // If delta-time is negative, the correction is in the opposite direction.
    amount = timeDeltaYears < 0 ? -amount : amount;
    auto result = spherePoint.offset(_offsetBearing * geom::radians, amount * geom::radians);
    Point newStar(star);
    newStar.x = result.getRa().asDegrees();
    newStar.y = result.getDec().asDegrees();
    return newStar;
}

operator=() [1/2]

ProperMotion & lsst::jointcal::ProperMotion::operator= ( ProperMotion && )

default

operator=() [2/2]

ProperMotion & lsst::jointcal::ProperMotion::operator= ( ProperMotion const & )

default

Friends And Related Symbol Documentation

operator<<

std::ostream & operator<< ( std::ostream & stream, ProperMotion const & pm )

friend

Definition at line 46 of file ProperMotion.cc.

                                                                   {
    stream << "pm_ra*cos(dec)=" << pm._ra << "rad/yr, pm_dec=" << pm._dec << "rad/yr, pm_raErr=" << pm._raErr
           << "rad/yr, pm_decErr=" << pm._decErr << "rad/yr, pm_raDecCov=" << pm._raDecCov;
    return stream;
}

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-12.0.0/Linux/jointcal/g29ae962dfc+1eb4aece83/include/lsst/jointcal/ProperMotion.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-12.0.0/Linux/jointcal/g29ae962dfc+1eb4aece83/src/ProperMotion.cc