# Sky2Pix_ConicEquidistant¶

class astropy.modeling.projections.Sky2Pix_ConicEquidistant(*args, **kwargs)[source]

Conic equidistant projection - sky to pixel.

Corresponds to the COD projection in FITS WCS.

See Conic for a description of the entire equation.

The projection formulae are:

$\begin{split}C &= \frac{180^\circ}{\pi} \frac{\sin\theta_a\sin\eta}{\eta} \\ R_\theta &= \theta_a - \theta + \eta\cot\eta\cot\theta_a \\ Y_0 = \eta\cot\eta\cot\theta_a\end{split}$
Parameters
sigmafloat

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

deltafloat

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

Methods Summary

 evaluate(phi, theta, sigma, delta) Evaluate the model on some input variables.

Methods Documentation

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

Evaluate the model on some input variables.