slant_orthographic-1.1.0
The slant orthographic projection.
Description
Corresponds to the SIN projection in the FITS WCS standard.
See zenithal for the definition of the full transformation.
The pixel-to-sky transformation is defined as:
\[\theta = \cos^{-1}\left(\frac{\pi}{180^{\circ}}R_\theta\right)\]
And the sky-to-pixel transformation is defined as:
\[R_\theta = \frac{180^{\circ}}{\pi}\cos \theta\]
Invertibility: All ASDF tools are required to provide the inverse of this transform.
Outline
Schema Definitions ¶
This node must validate against all of the following:
This type is an object with the following properties:
xi
object Obliqueness parameter, first equation of the slant orthographic projection.
This node must validate against any of the following:
number
eta
object Obliqueness parameter, second equation of the slant orthographic projection.
This node must validate against any of the following:
number
Original Schema ¶
%YAML 1.1
---
$schema: "http://stsci.edu/schemas/yaml-schema/draft-01"
id: "http://stsci.edu/schemas/asdf/transform/slant_orthographic-1.1.0"
title: |
The slant orthographic projection.
description: |
Corresponds to the `SIN` projection in the FITS WCS standard.
See
[zenithal](ref:schemas/zenithal-1.1.0)
for the definition of the full transformation.
The pixel-to-sky transformation is defined as:
$$\theta = \cos^{-1}\left(\frac{\pi}{180^{\circ}}R_\theta\right)$$
And the sky-to-pixel transformation is defined as:
$$R_\theta = \frac{180^{\circ}}{\pi}\cos \theta$$
Invertibility: All ASDF tools are required to provide the inverse of
this transform.
allOf:
- $ref: "zenithal-1.1.0"
- type: object
properties:
xi:
anyOf:
- $ref: "../unit/quantity-1.1.0"
- type: number
description: Obliqueness parameter, first equation of the slant
orthographic projection.
default: 0
eta:
anyOf:
- $ref: "../unit/quantity-1.1.0"
- type: number
description: Obliqueness parameter, second equation of the slant
orthographic projection.
default: 0
...