Class SkySys

java.lang.Object
uk.ac.starlink.ttools.plot2.geom.SkySys

public class SkySys extends Object
Sky coordinate system definition. These are used to label the system in which sky coordinates are supplied or required by SkyDataGeom so that a transformation can be performed between them if required. It is not an all-singing all-dancing toolkit for sky coordinate system manipulation.
Since:
20 Feb 2013
Author:
Mark Taylor
See Also:
  • Field Details

    • EQUATORIAL

      public static final SkySys EQUATORIAL
      J2000 Equatorial sky system.
    • GALACTIC

      public static final SkySys GALACTIC
      IAU 1958 Galactic sky system.
    • SUPERGALACTIC

      public static final SkySys SUPERGALACTIC
      De Vaucouleurs supergalactic system.
    • ECLIPTIC2000

      public static final SkySys ECLIPTIC2000
      Ecliptic system, based on conversion at data 2000.0. Probably not respectable.
  • Method Details

    • getSysName

      public String getSysName()
      Returns the name for this system.
      Returns:
      name
    • getSysDescription

      public String getSysDescription()
      Returns the description for this system.
      Returns:
      description
    • toEquatorial

      public double[] toEquatorial()
      Returns a rotation matrix to convert coordinates in this system to J2000 equatorial coordinates.
      Returns:
      9-element rotation matrix
    • getCoordPair

      public int[] getCoordPair(uk.ac.starlink.table.ValueInfo[] infos)
      Tries to guess at a pair of columns from a given selection that represent the longitude, latitude coordinates in this sky system.
      Parameters:
      infos - array of metadata items for the available columns
      Returns:
      2-element array giving indexes into infos array of lon,lat items, or null if attempt fails
    • toString

      public String toString()
      Overrides:
      toString in class Object
    • getKnownSystems

      public static SkySys[] getKnownSystems(boolean includeNull)
      Returns the list of known sky system instances.
      Parameters:
      includeNull - true if null is to appear in the list
      Returns:
      list of instances