Coordinate system description
Functions are available for converting Frame coordinate values into a form suitable for display, and also for calculating distances and offsets between positions within the Frame.
Frames may also contain knowledge of how to transform to and from related coordinate systems.
AlignSystem: Coordinate system used to align Frames
Bottom(axis): Lowest axis value to display
Digits/Digits(axis): Number of digits of precision
Direction(axis): Display axis in conventional direction?
Domain: Coordinate system domain
Dtai: Difference between the TAI and UTC timescale
Dut1: Difference between the UT1 and UTC timescale
Epoch: Epoch of observation
Format(axis): Format specification for axis values
InternalUnit(axis): Physical units for unformated axis values
Label(axis): Axis label
MatchEnd: Match trailing axes?
MaxAxes: Maximum number of Frame axes to match
MinAxes: Minimum number of Frame axes to match
Naxes: Number of Frame axes
NormUnit(axis): Normalised physical units for formatted axis values
ObsAlt: Geodetic altitude of observer
ObsLat: Geodetic latitude of observer
ObsLon: Geodetic longitude of observer
Permute: Permute axis order?
PreserveAxes: Preserve axes?
Symbol(axis): Axis symbol
System: Coordinate system used to describe the domain
Title: Frame title
Top(axis): Highest axis value to display
Unit(axis): Physical units for formatted axis values
astAngle: Calculate the angle subtended by two points at a third point
astAxAngle: Find the angle from an axis, to a line through two points
astAxDistance: Calculate the distance between two axis values
astAxNorm: Normalises an array of axis values
astAxOffset: Calculate an offset along an axis
astConvert: Determine how to convert between two coordinate systems
astDistance: Calculate the distance between two points in a Frame
astFindFrame: Find a coordinate system with specified characteristics
astFormat: Format a coordinate value for a Frame axis
astGetActiveUnit: Determines how the Unit attribute will be used
astIntersect: Find the intersection between two geodesic curves
astMatchAxes: Find any corresponding axes in two Frames
astNorm: Normalise a set of Frame coordinates representing one point
astNormPoints: Normalise a collection of points
astOffset: Calculate an offset along a geodesic curve
astOffset2: Calculate an offset along a geodesic curve in a 2D Frame
astPermAxes: Permute the order of a Frame’
s axes
astPickAxes: Create a new Frame by picking axes from an existing one
astResolve: Resolve a vector into two orthogonal components
astSetActiveUnit: Specify how the Unit attribute should be used
astUnformat: Read a formatted coordinate value for a Frame axis
AST_NORMPOINTS: Normalise a collection of points