Class lsst::jointcal::AstrometryTransform

class AstrometryTransform

a virtual (interface) class for geometric transformations.

We implement here One AstrometryTransform interface class, and actual derived classes. Composition in the usual (mathematical) sense is provided using compose(), and some classes (e.g. AstrometryTransformLinear

) handle a * operator. Generic inversion by iteration exists, but it is at least 10 times slower than the corresponding “direct

transformation”. If a transform has an analytical inverse, then providing inverseTransform is obviously a very good idea. Before resorting to inverseTransform, consider using

StarMatchList::inverseTransform(). AstrometryTransformLinear::inverted() and TanPixelToRaDec::inverted() exist. The classes also provide derivation and linear approximation.

Subclassed by lsst::jointcal::AstrometryTransformIdentity, lsst::jointcal::AstrometryTransformPolynomial, lsst::jointcal::AstrometryTransformSkyWcs, lsst::jointcal::BaseTanWcs, lsst::jointcal::TanRaDecToPixel, lsst::jointcal::UserTransform