Class TanRaDecToPixel

Inheritance Relationships

Base Type

Class Documentation

class TanRaDecToPixel : public lsst::jointcal::AstrometryTransform

This one is the Tangent Plane (called gnomonic) projection (from celestial sphere to tangent plane)

this transform does not implement corrections, since they are defined the other way around (from pixels to sky), and not invertible analytically. The inversion of tangent point WCS (TanPixelToRaDec) is obtained via inverseTransform().

Public Functions

TanRaDecToPixel(AstrometryTransformLinear const &tan2Pix, Point const &tangentPoint)

assume degrees everywhere.

TanRaDecToPixel()
AstrometryTransformLinear getLinPart() const

The Linear part (corresponding to CD’s and CRPIX’s)

void setTangentPoint(Point const &tangentPoint)

Resets the projection (or tangent) point.

Point getTangentPoint() const

tangent point coordinates (degrees)

void apply(const double xIn, const double yIn, double &xOut, double &yOut) const
void transformPosAndErrors(const FatPoint &in, FatPoint &out) const

transform with analytical derivatives

TanPixelToRaDec inverted() const

exact typed inverse:

std::unique_ptr<AstrometryTransform> roughInverse(const Frame &region) const

Overload the “generic routine” (available for all AstrometryTransform types.

std::unique_ptr<AstrometryTransform> inverseTransform(const double precision, const Frame &region) const

Inverse transform: returns a TanPixelToRaDec.

void dump(std::ostream &stream) const

dumps the transform coefficients to stream.

std::unique_ptr<AstrometryTransform> clone() const

returns a copy (allocated by new) of the transformation.

double fit(StarMatchList const &starMatchList)

fits a transform to a std::list of Point pairs (p1,p2, the Point fields in StarMatch).

After the fit this(p1) yields approximately p2. The returned value is the sum of squared residuals. If you want to fit a partial transform (e.g. such that this(T1(p1)) = T2(p2), use StarMatchList::applyTransform beforehand.