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- Sky2Pix_Parabolic

# Sky2Pix_Parabolic

class astropy.modeling.projections.Sky2Pix_Parabolic(*args, **kwargs)

  Bases: `Sky2PixProjection`, `PseudoCylindrical`

  Parabolic projection - sky to pixel.

  Corresponds to the `PAR` projection in FITS WCS.

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