AixmDataSet Class
A dataset for reading aeronautical information from AIXM 5.1 and 5.1.1 files.
NuGet/Assembly: Carmenta.Engine.5.16.2.nupkg (in the CEDataSets assembly)
Syntax
public class AixmDataSet : MultiFileDataSet,
ISearchableRemarks
This dataset reads aeronautical data from AIXM files, see http://www.aixm.aero/page/aixm-51-specification. Supported AIXM versions are 5.1 and 5.1.1. The dataset will read the following feature types:
Designated points
Navaids
Airports and heliports
Runways
Airspaces
Routes
Standard instrument arrivals (STARs), departures (SIDs) and approach procedures
Limitations
The temporality model in AIXM 5 is only partially supported. The dataset can read multiple AIXM files and all "baseline" feature time slices will be read and handled correctly. But other types of time slices ("permdelta", "tempdelta", "snapshot") will be ignored.
The Time property can be used to select time slices for a particular moment in time, but it must be specified before the dataset is initialized and can't be changed afterwards.
The complex object model in AIXM can't be properly expressed in terms of Carmenta Engine features. The dataset will simply create a flat list of features, copying information from referenced objects when needed.
References between objects are supported locally within a file, and also between different AIXM files. But for instance references to AIXM documents on web servers are not supported. All references that can't be resolved will be silently ignored, and parts of or complete features will be dropped if the information is incomplete.
SIDs, STARs and approach procedures may be specified with pre-calculated geometries in the data files; if so those geometries are used. If not, the procedures will only consist of the start and end points of the legs, with straight lines in between.
Index files
The dataset uses a two-stage feature index. First, each input file is parsed and the needed information is extracted. This is then saved as a feature index under FeatureIndexPath, one file per AIXM input file.
But since the records defining a single AIXM feature may be spread out across multiple files, a dataset-wide feature index is also built, and saved next to the file index under IndexPath, with file extension ".carmentavectorcache". This is created by combining the intermediate index files, selecting time slices for a specified time, resolving all references and preprocessing the feature geometries where possible.
This means that the index file actually depends on the Time property of the dataset. When the dataset is initialized, it will check if an existing file is valid for the specified time. If the index file is not valid an exception will be thrown, or, if VerifyIndexFiles is True, the index file be regenerated.
Since the complete index can be quite large, keeping it all in memory is not supported. Therefore, the IndexPath property must be specified for this dataset. Specifying FeatureIndexPath is still optional; if not specified it will take longer to regenerate the complete index if the dataset time is changed.
Detailed list of feature types and attributes
All features carry an aixm_type attribute that can be used for filtering out uninteresting object types and thereby increase performance, see the tables below and the AixmQuery class.
Designated points
One Carmenta Engine point feature for each AIXM DesignatedPoint record.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #DesignatedPoint |
designator | String | The coded designator of the point. For example, the five-letter ICAO name of the point, etc. |
name | String | The full textual name of a designated point, if any. For example, 'GOTAN Intersection' for GOTAN. |
type | Atom | The kind of point designator, indicating the rules by which the designator has been created. |
Navaids
A navaid feature is created from an AIXM Navaid record, plus zero of more NavaidEquipment records. Only the most common NavaidEquipment records are read (VOR, DME, NDB, TACAN). Properties from all records are added to a single Carmenta Engine point feature.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #Navaid |
designator | String | The coded identifier given to the navaid system. |
name | String | The long name given to the composite navaid. |
type | Atom | Type of the navaid service such as ILS, MLS, VORTAC, VOR/DME, etc. |
purpose | Atom | Indication of the intended usage of the navaid (enroute or terminal)- |
vor_type | Atom | A code indicating the type of a VOR navaid equipment, e.g. conventional VOR or Doppler VOR. |
vor_frequency | Double | The frequency used by a VOR navaid equipment. |
vor_frequency_uom | Atom | Unit of measure of the vor_frequency attribute. |
dme_type | Atom | The particular spectrum characteristics or accuracy of a DME navaid equipment, as a category. |
dme_channel | String | The channel used by a DME navaid equipment. |
ndb_class | Atom | The class of an NDB navaid equipment. For example, NDB or Locator. |
ndb_frequency | Double | The frequency used by an NDB navaid equipment emission. |
ndb_frequency_uom | Atom | Unit of measure of the ndb_frequency attribute. |
tacan_channel | String | The channel used by a TACAN navaid equipment. |
Airports/heliports
One Carmenta Engine point feature for each AIXM AirportHeliport record.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #AirportHeliport |
designator | String | A designator for an airport/heliport. |
designator_iata | String | The identifier that is assigned to a location in accordance with rules (resolution 767) governed by the International Air Transport Association (IATA). |
name | String | The primary official name of an airportheliport as designated by an appropriate authority. |
type | Atom | The type of airportheliport. For example, aerodrome only, combined aerodrome/heliport or simple landing site. |
Runways
Runway features are polygons with four corner points, created from runway threshold points, and length, width and bearing parameters.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #Runway |
designator | String | The designator of a runway, used to uniquely identify it at an aerodromeheliport. |
type | Atom | The type can be either runway for airplanes or Final Approach and Take-off Area (FATO) for helicopters. |
nominal_length | Double | The declared longitudinal extent of the runway for operational (performance) calculations, in meters. |
nominal_width | Double | The declared transversal extent of the runway for operational (performance) calculations, in meters. |
length_strip | Double | The physical length of the strip, in meters. |
width_strip | Double | The physical width of the strip, in meters. |
airport_designator | String | The designator of the airport the runway is associated with. |
airport_name | String | The name of the airport the runway is associated with. |
Airspaces
In AIXM, airspaces are defined as zero or more airspace volumes combined with zero or more other airspaces, using volume operations such as union, intersection or difference.
This is not supported by this dataset. Instead, each airspace volume creates one Carmenta Engine feature per polygon patch in the volume. For each volume, the corresponding airspace record is located, and feature attributes are combined from both the volume and airspace records. All features belonging to the same airspace will get the same Carmenta Engine feature ID.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #Airspace |
designator | String | A published sequence of characters allowing the identification of the airspace. |
name | String | The name given to an airspace by a responsible authority. It should be written as published, with no significance to upper or lower case letters. |
type | Atom | An indicator of the general structure or characteristics of a particular airspace. |
lower_limit | String | The vertical distance of the lower bound (floor) of the airspace volume. |
lower_limit_uom | Atom | Unit of measure of the lower_limit attribute. |
lower_limit_reference | Atom | The reference surface (Mean Sea Level, Ground, standard pressure, etc.) used for the value of the lower limit of the airspace volume. |
lower_limit_numeric | Double | The numeric value of the lower_limit and lower_limit_uom attributes, if possible to calculate, in meters. |
upper_limit | String | The vertical distance of the lower bound (floor) of the airspace volume. |
upper_limit_uom | Atom | Unit of measure of the upper_limit attribute. |
upper_limit_reference | Atom | The reference surface (Mean Sea Level, Ground, standard pressure, etc.) used for the value of the upper limit of the airspace volume. |
upper_limit_numeric | Double | The numeric value of the upper_limit and upper_limit_uom attributes, if possible to calculate, in meters. |
Route segments
These are line features representing one segment an AIXM route. Usually they only have two points, but extra points may be inserted on long segments specified as great circle routes or rhumb lines.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #RouteSegment |
level | Atom | A code indicating if the route segment is in the upper airspace, the lower airspace or both. |
direction | Atom | A code indicating if the route segment is available in the forward direction, backward direction, or both. |
lower_limit | String | The vertical position of the route segment floor. |
lower_limit_uom | Atom | Unit of measure of the lower_limit attribute. |
lower_limit_reference | Atom | The reference surface used for the value of the lower limit. For example, Mean Sea Level, Ground, standard pressure, etc. |
lower_limit_numeric | Double | The numeric value of the lower_limit and lower_limit_uom attributes, if possible to calculate, in meters. |
upper_limit | String | The vertical position of the route segment ceiling. |
upper_limit_uom | Atom | Unit of measure of the upper_limit attribute. |
upper_limit_reference | Atom | The reference surface used for the value of the upper limit. For example, Mean Sea Level, Ground, standard pressure, etc.. |
upper_limit_numeric | Double | The numeric value of the upper_limit and upper_limit_uom attributes, if possible to calculate, in meters. |
true_track | Double | The initial true track. |
magnetic_track | Double | The initial magnetic track. |
reverse_true_track | Double | The reverse initial true track. |
reverse_magnetic_track | Double | The reverse initial magnetic track. |
length | Double | The length of the path, in meters. |
route_designator | String | The designator of the route the segment is part of. |
route_name | String | The name of the route the segment is part of. |
Routes
Line features representing AIXM routes.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #Route |
designator | String | A designator for the route. |
name | String | A free text name by which the route is known. |
type | Atom | Route classification. |
Procedure legs
Line features representing one leg of a Standard Instrument Arrival (STAR), Standard Instrument Departure (SID) or Instrument Approach procedure. If the trajectory of the segment is included in the AIXM file, it will be used, otherwise the segment will only contain the start and end points.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #ArrivalLeg, #DepartureLeg or #ApproachLeg |
leg_type_arinc | Atom | A comprehensive description of the 'path and terminator' concept is given in ARINC Specification 424. |
course | Double | The value of the course angle in degrees. |
course_type | Atom | A code indicating the type of course to be observed. E.g. true track, magnetic track, heading, VOR radial, true bearing, magnetic bearing. |
length | Double | The length of the segment, in meters. |
lower_limit | String | The lower limit altitude. |
lower_limit_uom | String | Unit of measure of the lower_limit attribute. |
lower_limit_reference | String | A code indicating the reference for a vertical distance. |
lower_limit_numeric | Double | The numeric value of the lower_limit and lower_limit_uom attributes, if possible to calculate, in meters. |
upper_limit | String | The value of the upper altitude. |
upper_limit_uom | String | Unit of measure of the upper_limit attribute. |
upper_limit_reference | String | A code indicating the reference for a vertical distance. |
upper_limit_numeric | Double | The numeric value of the upper_limit and upper_limit_uom attributes, if possible to calculate, in meters. |
procedure_designator | String | The designator of the procedure the leg is part of. |
procedure_name | String | The name of the procedure the leg is part of. |
Procedures
Line features representing Standard Instrument Arrival (STAR), Standard Instrument Departure (SID) or Instrument Approach procedures. Each transition of the procedure will generate a separate feature, but with the same feature ID. If the trajectory of the transition is included in the AIXM file, it will be used, otherwise a line geometry will be built from the legs making up the procedure transition.
Attribute | Type | Description |
|---|---|---|
aixm_type | Atom | #StandardInstrumentArrival, #StandardInstrumentDeparture or #InstrumentApproachProcedure |
designator | String | The textual designator of the SID or STAR. Not used for approach procedures. |
approach_prefix | String | Prefix used in support of current naming conventions. Not used by SID or STAR. |
approach_type | Atom | A name describing the type of radio navigational aid/system. |
multiple_identification | String | One character code for multiple approaches of the same approach type; Z-A. |
name | String | The name of the instrument procedure. |
transition_id | String | Used strictly for ARINC coding. The identifier will be the initial point for each transition. |
transition_type | Atom | The type of transition. |
Inheritance Hierarchy
System.Object (not available in C#)
EngineObject
ResourceObject
DataSet
FileDataSet
MultiFileDataSet
AixmDataSet
Platforms
Windows, Linux, Android
AixmDataSet Members
The AixmDataSet type has the following members.
Constructors
| Name | Description |
|---|---|
| AixmDataSet | Initializes a new instance of the AixmDataSet class with the given path and filename. |
Properties
| Name | Description |
|---|---|
| Description | Gets or sets a short description of the dataset. Inherited from DataSet |
| DisplayName | Gets or sets a display name for the dataset. Inherited from DataSet |
| FeatureIndexPath | Gets or sets the directory where the intermediate feature index files will be saved. |
| FileName | Gets or sets the name of the file to read from. Inherited from FileDataSet |
| ISearchable.HasSearchIndex | Gets a value that tells whether a dataset has a search index. Inherited from ISearchable |
| Id | Gets a unique identifier for this dataset instance. Inherited from DataSet |
| IndexFileName | Gets or sets an explicit index file name used for the generated index files in IndexPath. Inherited from MultiFileDataSet |
| IndexPath | Gets or sets the directory where the dataset index files are saved. Inherited from MultiFileDataSet |
| IsDisposed | Gets a value that tells whether the current AixmDataSet has been disposed. Inherited from EngineObject |
| IsoMetadataDocument | Gets or sets the path to an ISO 19139 metadata document for the dataset. Inherited from DataSet |
| Name | Gets or sets the name of the AixmDataSet. Inherited from ResourceObject |
| NativeHandle | Gets the native Carmenta Engine kernel object the current AixmDataSet represents. Inherited from EngineObject |
| Path | Gets or sets the path to the file or files to read from. Inherited from FileDataSet |
| SearchableAttributes | The attributes that will be used to create a search index for the dataset. |
| SearchableCondition | Gets or sets a condition that determines which features will be included in the search index for the dataset. |
| SearchSubdirectories | Gets or sets a flag indicating if the dataset will search for data files recursively. Inherited from MultiFileDataSet |
| SuppressInitializationErrors | Gets or sets a flag indicating how errors during dataset initialization are handled. Inherited from DataSet |
| Time | Gets or sets the time to read AIXM data for. |
| IUserProperties.UserProperties | Gets the AttributeSet that contains the user properties. Inherited from IUserProperties |
| VerifyIndexFiles | Gets or sets a flag indicating if the contents of index files should be verified before use. Inherited from MultiFileDataSet |
Methods
| Name | Description |
|---|---|
| Clone | Creates a copy of an object. Inherited from EngineObject |
| Dispose | Releases the reference to the native Carmenta Engine kernel instance the EngineObject represents. Inherited from EngineObject |
| Equals | Determines whether this instance is equal to another. Inherited from EngineObject |
| FindChildObject | Overloaded. Finds the child object with the specified name. Inherited from DataSet |
| FlushCache | Frees any information the dataset may have cached, including all cached features. Inherited from DataSet |
| GetChildObjects | Overloaded. Gets the child objects of the current object. Inherited from DataSet |
| GetDataCoverage | Gets coverage information for this dataset in a given area. Inherited from DataSet |
 GetDataSetById | Looks up an existing dataset instance from a dataset identity. Inherited from DataSet |
| GetDataSetInfo | Returns a dataset info that describes the contents of this dataset. Inherited from DataSet |
| GetDataSetInfoAsync | Makes an asynchronous call to GetDataSetInfo. Inherited from DataSet |
| GetFeature | Gets the feature with the specified identity. Inherited from DataSet |
| GetFeatures | Overloaded. Gets features from the dataset. Inherited from DataSet |
| GetFloatValueAt | Overloaded. Gets the float raster value from a cell at the specified position. Inherited from DataSet |
| GetFloatValuesAt | Overloaded. Gets a number of float raster values. Inherited from DataSet |
| GetLocalizedDescription | Gets a localized version of the dataset description in a specific language. Inherited from DataSet |
| GetLocalizedDisplayName | Gets a localized version of the dataset display name in a specific language. Inherited from DataSet |
| GetLocalizedIsoMetadataDocument | Gets the path to an ISO 19139 metadata document for a specific language. Inherited from DataSet |
| GetNormalizedFloatValueAt | Overloaded. Gets the raster value from a cell at the specified position, normalized by Scale and Offset. Inherited from DataSet |
| GetNormalizedFloatValuesAt | Overloaded. Gets a number of raster values, normalized by Scale and Offset. Inherited from DataSet |
| GetValueAt | Overloaded. Gets the integer value from a raster cell at the specified position. Inherited from DataSet |
| GetValuesAt | Overloaded. Gets a number of raster values. Inherited from DataSet |
| HasLocalizedDescription | Checks if a localized version of the dataset description is available in a specific language. Inherited from DataSet |
| HasLocalizedDisplayName | Checks if a localized version of the dataset display name is available in a specific language. Inherited from DataSet |
| HasLocalizedIsoMetadataDocument | Checks if an ISO 19139 metadata document is available for a specific language. Inherited from DataSet |
| HighestRasterValue | Finds the highest raster value inside the given polygon. Inherited from DataSet |
| Initialize | Initializes the dataset. Inherited from DataSet |
| ISearchable.Search | Overloaded. Searches for features with an attribute whose value match the specified search text. Inherited from ISearchable |
| SetLocalizedDescription | Sets a dataset description in a specific language. Inherited from DataSet |
| SetLocalizedDisplayName | Sets a dataset display name in a specific language. Inherited from DataSet |
| SetLocalizedIsoMetadataDocument | Sets the path to an ISO 19139 metadata document for the dataset, for a specific language. Inherited from DataSet |
| TryGetFloatValueAt | Overloaded. Gets the float value from a raster cell at the specified position. Inherited from DataSet |
| TryGetNormalizedFloatValueAt | Overloaded. Gets the float value from a raster cell at the specified position, normalized by Scale and Offset. Inherited from DataSet |
| TryGetValueAt | Overloaded. Gets the integer value from a raster cell at the specified position. Inherited from DataSet |