Depth Below Entrance Datum Converter
Signed station depth below actual common-datum entrance; negative means above entrance, not absolute cave-depth record.
Description
Depth below an entrance datum subtracts station elevation from entrance elevation.
Depth below an entrance datum subtracts station elevation from entrance elevation.1
A station above the entrance produces a negative depth under this signed convention.
When to use Depth Below Entrance Datum Converter
Use this tool to obtain signedDepthBelowEntranceMeters from the supplied records using the stated calculation. Establish the survey or observation scope, reference frame, units and independently applicable calibration or qualified plan.
How to use Depth Below Entrance Datum Converter and understand its results
- Establish the survey or observation scope, reference frame, units and independently applicable calibration or qualified plan.
- Enter actualEntranceDatumElevationMeters, actualStationElevationMeters, using the field meanings and rules below, then run the tool.
- Read result.signedDepthBelowEntranceMeters. Use the units and sign conventions below, and review any unknown records separately.
- Correct any reported input issue and run again. Before using a successful result, check the stated units, signs, reference scope and observation coverage.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualEntranceDatumElevationMeters | Actual entrance datum elevation meters | number | Required |
| actualStationElevationMeters | Actual station elevation meters | number | Required |
Enter two finite elevations in metres on a common datum. Subtract station elevation from entrance elevation; signed inputs and a negative result are accepted.
depthBelowEntranceMeters=entranceElevation−stationElevation Use the matching field units and the exact boundary, ordering and reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Qualified observed calculation or explicit reference | object |
| result.signedDepthBelowEntranceMeters | Signed Depth Below Entrance Meters; preserve the subtraction order and sign defined in the mechanics | number |
{
"input": {
"actualEntranceDatumElevationMeters": 10,
"actualStationElevationMeters": 3
},
"output": {
"result": {
"signedDepthBelowEntranceMeters": 7
}
}
}Limitations and assumptions
The actual observation coverage, calibration and qualified plan determine applicability. A numerical result does not establish survey accuracy, route suitability, atmosphere conditions or equipment adequacy beyond the declared comparison.
Missing required fields, unknown fields, wrong types and violated rules return input issues. Numeric values and outputs must be finite. Extremely large composite outputs are rejected.
Alternative or Complementary methods
For a related step, use Grid Reference to Survey Coordinate Converter: A grid reference belongs to a coordinate system, zone, datum and origin. For a complementary comparison, use Survey Shot 3D Coordinate Calculator: A cave survey shot relates a measured distance, azimuth and inclination to a Cartesian displacement.
References
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Depth Below Entrance Datum Converter — tool.io
Similar or alternative tools
- Grid Reference to Survey Coordinate Converter
A grid reference belongs to a coordinate system, zone, datum and origin.
- Survey Shot 3D Coordinate Calculator
A cave survey shot relates a measured distance, azimuth and inclination to a Cartesian displacement.