Pix2Sky_Parabolic¶

class astropy.modeling.projections.Pix2Sky_Parabolic(*args, **kwargs)[source]¶

Parabolic projection - pixel to sky.

Corresponds to the PAR projection in FITS WCS.

\[\begin{split}\phi &= \frac{180^\circ}{\pi} \frac{x}{1 - 4(y / 180^\circ)^2} \\ \theta &= 3 \sin^{-1}\left(\frac{y}{180^\circ}\right)\end{split}\]