skycells-1.1.0

Skycells Reference File Schema

Outline

Schema Definitions

This type is an object with the following properties:

  • meta

    objectRequired

    Metadata for Skycells definitions reference file

    The necessary metadata for the Skycells reference file

    This node must validate against all of the following:

    • This type is an object with the following properties:

      • reftype

        string

        Reference File Type

        The capitalized string of the reference file type (e.g., DARK).

        No length restriction

        Only the following values are valid for this node:

        • SKYCELLS

      • pedigree

        string

        Pedigree

        The pedigree of the reference file (e.g., GROUND).

        No length restriction

        Only the following values are valid for this node:

        • GROUND

      • description

        string

        Description

        A string describing the reference file, its intended usage, etc.

        No length restriction

      • author

        string

        Author

        The author of who or what created the reference file.

        No length restriction

      • useafter

        tag:stsci.edu:asdf/time/time-1.*

        Use After Date

        The use after date of the reference file for CRDS best references matching.

      • telescope

        asdf://stsci.edu/datamodels/roman/schemas/meta/telescope-1.0.0

      • origin

        string

        Organization

        The organization responsible for creating the file, e.g. STSCI for the Space Telescope Science Institute.

        No length restriction

      • instrument

        object

        This type is an object with the following properties:

        • name

          string

          Instrument

          The Wide Field Instrument (WFI).

          No length restriction

          Only the following values are valid for this node:

          • WFI

      • nxy_skycell

        integer

        Number of pixels in both x and y dimensions

        The shape of the skycell is (nxy_skycell, nxy_skycell)

      • skycell_border_pixels

        integer

        The number of pixels in all directions that overlap with the adjacent skycell.

        Within a projection region, skycells are tiled on the same global pixel grid; this value indicates how many pixels are overlapped in all directions in this tiling.

      • pixel_scale

        number

        The size of a pixel at the tangent point in arcseconds

        The size of the pixel at the tangent point as projected on the sky in linear pixels for both directions (e.g., it is assumed equal for both directions).

  • projection_regions

    tag:stsci.edu:asdf/core/ndarray-1.*Required

    Information about each projection region

    A structured array that contains relevant information about all the projection regions that cover the entire celestial sphere.

  • skycells

    tag:stsci.edu:asdf/core/ndarray-1.*Required

    Information about all skycells

    Relevant information about all skycells that have been defined to cover the celestial sphere.

Original Schema 

%YAML 1.1
---
$schema: asdf://stsci.edu/datamodels/roman/schemas/rad_schema-1.0.0
id: asdf://stsci.edu/datamodels/roman/schemas/reference_files/skycells-1.1.0

title: Skycells Reference File Schema

datamodel_name: SkycellsRefModel

type: object
properties:
  meta:
    title: Metadata for Skycells definitions reference file
    description: |
      The necessary metadata for the Skycells reference file
    allOf:
      - type: object
        properties:
          reftype:
            title: Reference File Type
            description: |
              The capitalized string of the reference file type (e.g., DARK).
            type: string
            enum: [SKYCELLS]
          pedigree:
            title: Pedigree
            description: |
              The pedigree of the reference file (e.g., GROUND).
            type: string
            enum: [GROUND]
          description:
            title: Description
            description: |
              A string describing the reference file, its intended usage, etc.
            type: string
          author:
            title: Author
            description: |
              The author of who or what created the reference file.
            type: string
          useafter:
            title: Use After Date
            description: |
              The use after date of the reference file for CRDS best references
              matching.
            tag: tag:stsci.edu:asdf/time/time-1.*
          telescope:
            $ref: asdf://stsci.edu/datamodels/roman/schemas/meta/telescope-1.0.0
          origin:
            title: Organization
            description: |
              The organization responsible for creating the file, e.g. STSCI for the
              Space Telescope Science Institute.
            type: string
          instrument:
            type: object
            properties:
              name:
                title: Instrument
                description: |
                  The Wide Field Instrument (WFI).
                type: string
                enum: [WFI]
          nxy_skycell:
            title: Number of pixels in both x and y dimensions
            description: |
              The shape of the skycell is (nxy_skycell, nxy_skycell)
            type: integer
          skycell_border_pixels:
            title: The number of pixels in all directions that overlap with the adjacent skycell.
            description: |
              Within a projection region, skycells are tiled on the same global pixel grid;
              this value indicates how many pixels are overlapped in all directions in this tiling.
            type: integer
          pixel_scale:
            title: The size of a pixel at the tangent point in arcseconds
            description: |
              The size of the pixel at the tangent point as projected on the sky in linear pixels for
              both directions (e.g., it is assumed equal for both directions).
            type: number
  projection_regions:
    tag: tag:stsci.edu:asdf/core/ndarray-1.*
    title: Information about each projection region
    description: |
      A structured array that contains relevant information about all the projection regions that
      cover the entire celestial sphere.
    datatype:
      - name: index
        datatype: int32
        byteorder: little
      - name: ra_tangent
        datatype: float64
        byteorder: little
      - name: dec_tangent
        datatype: float64
        byteorder: little
      - name: ra_min
        datatype: float64
        byteorder: little
      - name: ra_max
        datatype: float64
        byteorder: little
      - name: dec_min
        datatype: float64
        byteorder: little
      - name: dec_max
        datatype: float64
        byteorder: little
      - name: orientat
        datatype: float32
        byteorder: little
      - name: x_tangent
        datatype: float64
        byteorder: little
      - name: y_tangent
        datatype: float64
        byteorder: little
      - name: nx
        datatype: int32
        byteorder: little
      - name: ny
        datatype: int32
        byteorder: little
      - name: skycell_start
        datatype: int32
        byteorder: little
      - name: skycell_end
        datatype: int32
        byteorder: little
    exact_datatype: true
  skycells:
    tag: tag:stsci.edu:asdf/core/ndarray-1.*
    title: Information about all skycells
    description: |
      Relevant information about all skycells that have been defined to cover the celestial sphere.
    datatype:
      - name: name
        datatype: [ucs4, 16]
        byteorder: little
      - name: ra_center
        datatype: float64
        byteorder: little
      - name: dec_center
        datatype: float64
        byteorder: little
      - name: orientat
        datatype: float32
        byteorder: little
      - name: x_tangent
        datatype: float64
        byteorder: little
      - name: y_tangent
        datatype: float64
        byteorder: little
      - name: ra_corn1
        datatype: float64
        byteorder: little
      - name: dec_corn1
        datatype: float64
        byteorder: little
      - name: ra_corn2
        datatype: float64
        byteorder: little
      - name: dec_corn2
        datatype: float64
        byteorder: little
      - name: ra_corn3
        datatype: float64
        byteorder: little
      - name: dec_corn3
        datatype: float64
        byteorder: little
      - name: ra_corn4
        datatype: float64
        byteorder: little
      - name: dec_corn4
        datatype: float64
        byteorder: little
    exact_datatype: true
required: [meta, projection_regions, skycells]
flowStyle: block
propertyOrder: [meta, projection_regions, skycells]