The DensityData model data is a common datatype for acoustic and swept-area density produced by the functions AcousticDensity and SweptAreaDensity, respectively, and contains the tables Data and Resolution with variables given in the following tables:
Data:
| Variable | Description | Unit | Data type | Example | Occurrence |
| Survey | The survey identifier | None | Character | "MainSurvey" | Always |
| Stratum | The stratum identifier | None | Character | "Stratum1" | Always |
| PSU | The PSU identifier | None | Character | "PSU1" | Always |
| Layer | The depth Layer identifier | None | Character | "Layer1" | Always |
| Beam | Unique Beam identifier | None | Character | "38000/2" | AcousticDensity |
| SpeciesCategory | The species category | None | Character | "Herring" | Always |
| IndividualTotalLength | Total length (from snout to end of fin), given as the lower end of the interval of width given by LengthResolution | cm | Numeric | 14.5 | SweptAreaDensity |
| LengthResolution | Resolution of IndividualTotalLength | cm | Numeric | 0.5 | SweptAreaDensity |
| Frequency | The acoustic frequency of the Beam | hertz | Numeric | 38000 | AcousticDensity |
| Density | The density, either given as number of individuals or weight per square nautical mile (when DensityType is "AreaNumberDensity" or AreaWeightDensity, respectively) | nmi^-2 if DensityType is "AreaNumberDensity", and kg nmi^-2 if DensityType is "AreaWeightDensity" (only relevant when SweptAreaDensityMethod is "TotalCatch") | Numeric | 123.4 | Always |
| MinLayerDepth | The minimum depth of the depth Layer | m | Numeric | 0 | Always |
| MaxLayerDepth | The maximum depth of the depth Layer | m | Numeric | 100 | Always |
| DensityWeight | The weight of the density value associated with the PSU, i.e., the number of Stations for SweptAreaDensity and total LogDistance for AcousticDensity | None | Numeric | 8 | Always |
| DensityType | The type of density, currently one of "AreaNumberDensity" and "AreaWeightDensity" | None | Character | "AreaNumberDensity" | Always |
Resolution:
| Variable | Description | Unit | Data type | Example | Occurrence |
| Stratum | The stratum identifier | None | Character | "Stratum1" | Always |
| PSU | The PSU identifier | None | Character | "PSU1" | Always |
| EDSU | Unique elementary distance sampling unit (EDSU/Log) identifier | None | Character | "2020821/2020-04-24T03:51:26.000Z" | AcousticDensity |
| Station | Unique Station identifier | None | Character | "2021105-1" | SweptAreaDensity |
| Layer | The depth Layer identifier | None | Character | "Layer1" | Always |
| Channel | Unique NASC depth channel identifier | None | Character | "2" | AcousticDensity |
| Cruise | Unique Cruise identifier (see StoxAcousticFormat for output from AcousticDensity and StoxBioticFormat for output from SweptAreaDensity) | None | Character | "2021105" | Always |
| EffectiveLogDistance | The effective length of the EDSU | nmi | Numeric | 0.09 | AcousticDensity |
| EffectiveTowDistance | Effective tow distance of the Haul | nmi | Numeric | 1.5 | SweptAreaDensity |
| DateTime | UTC time at start of the EDSU or Station, stored as POSIXct | ISO8601 | Character | 2020-09-09T01:02:03.456Z | Always |
| Longitude | Longitude at start of the EDSU or Station | degree east | Numeric | 62.5 | Always |
| Latitude | Latitude at start of the EDSU or Station | degree north | Numeric | 5.1 | Always |
| VerticalNetOpening | Vertical span of the net | m | Numeric | 23 | SweptAreaDensity |
| HorizontalNetOpening | Vertical span of the net | m | Numeric | 105 | SweptAreaDensity |
| TrawlDoorSpread | Distance between the trawl doors. | m | Numeric | 125 | SweptAreaDensity |
This data type is produced by AcousticDensity and SweptAreaDensity. See DataTypes for a list of all StoX data types produced by RstoxBase.