File Format - DTA
File Format - DTA
Purpose
DTA is an ESCS Survey Control Data File format. In HAPI, it is used to update or represent Survey Control Points rather than ordinary topographic survey shots.
General Architecture
DTA is comma-delimited and contains control station data. It should be parsed using CSV-safe logic rather than fixed-width slicing.
Delimited Anatomy
| Index | Field | Meaning |
|---|---|---|
[0] | Point Name / Full Control Station ID | Survey control identity. |
[1] | Northing | Y-coordinate. |
[2] | Easting | X-coordinate. |
[3] | Reduced Level | Z-coordinate. |
Business Logic
| Rule | Meaning |
|---|---|
| Survey Control only | DTA does not represent standard topographic shots. |
| Forced Feature Code | Imported records should be treated as STN. |
| Existing control update | A1a automatically updates existing Survey Control Points when importing DTA data. |
Edge Cases
- Missing or blank reduced level should fall back to 0.000 where safe.
- Empty trailing rows should be ignored.
- DTA does not contain point numbers; any internal point-number placeholder is implementation-only and should not affect survey-control meaning.
Related Scripts
Source Basis
HAPI User Manual.pdf, Section 2.3.1.File Format - DTA File.md.
