Sky2Pix_ConicPerspective

class astropy.modeling.projections.Sky2Pix_ConicPerspective(sigma=90.0, delta=0.0, **kwargs)[source] [edit on github]

Bases: astropy.modeling.projections.Sky2PixProjection, astropy.modeling.projections.Conic

Colles’ conic perspective projection - sky to pixel.

Corresponds to the COP projection in FITS WCS.

See Conic for a description of the entire equation.

The projection formulæ are:

C &= \sin \theta_a \\ R_\theta &= \frac{180^\circ}{\pi} \cos \eta [ \cot \theta_a - \tan(\theta - \theta_a)] \\ Y_0 &= \frac{180^\circ}{\pi} \cos \eta \cot \theta_a

Parameters:

sigma : float

(\theta_1 + \theta_2) / 2, where \theta_1 and \theta_2 are the latitudes of the standard parallels, in degrees. Default is 90.

delta : float

(\theta_1 - \theta_2) / 2, where \theta_1 and \theta_2 are the latitudes of the standard parallels, in degrees. Default is 0.

Attributes Summary

param_names

Methods Summary

evaluate(phi, theta, sigma, delta)

Attributes Documentation

param_names = ('sigma', 'delta')

Methods Documentation

classmethod evaluate(phi, theta, sigma, delta)[source] [edit on github]