Traverse
File Editor: File/Extract(This functionality is available with the Input / Output module)
Extracts traverse observations from a selected Field File into the currently open Traverse File and displays them in the Traverse File Editor.
Traverse observations by definition consist of the following types which may be automatically extracted from a field file:
- Observations to an instrument set up point in the traverse;
- Observations to a fixed point of known co-ordinates at the start or end of a traverse;
- Observations to a reference object of unknown co-ordinates but of known bearing at the start or end of a traverse.
Note: Any operations contained in the field file which would affect the resulting position of the extracted observation are not applied in the extraction process. Such operations include left/right offset and add/reduce distance. Do not use such operations on control observations.
The following topics document the various commands and features of the Traverse File Editor.
The traverse observations may then be edited and adjusted using the traverse file editor to provide adjusted co-ordinates of the traverse points in the data base. Then, when the field file is reduced using the Field Transfer/Resolve/Reduce Field File command, these adjusted co-ordinates in the data base will be used in preference to any co-ordinates found in the field file, ensuring that the reduction of the field file is in accordance with the adjustment carried out.
Extract Traverse File dialog box
| Item | Used to |
| Look in: | Select the folder in which the traverse file is located. |
| File name: | Key in the name of the existing field file or to display a field file name selected from the Files list box. |
| Files of type: | Select the type of files to be displayed in the file list. |
| Apply Curvature & Refraction | Select whether earth curvature and refraction corrections are to be applied during the extraction
process. The refraction (K) value and earth curvature used to calculate the correction are those currently set in the Utilities/Configure/Earth constants command. The formula used is also found in that topic. |
| Mean all Verticals | Set whether all vertical circle observations observed as sets are to be used in calculating
the averages. Only sets of observations of field file record type 160 are used for this option. If checked, then all vertical circle readings observed as sets will be used whether observed with a distance or not. If the check box is not checked, then only vertical circle readings observed as sets and taken with a distance observation will be used. Leave the check box unchecked as a quality traverse measure to ensure that vertical circle readings used were all taken to the prism. |
| OK | Extract the traverse observations from the selected field file into the currently open traverse
file, and close the dialog box. The OK button is only active after a traverse file has been selected. The extracted data is displayed in the traverse file editor. |
| Cancel | Close the dialog box without extracting the traverse observations. |
Directions extracted from the field file which were observed on datum (i.e. without a backsight point identifier and direction) are passed to the traverse file as bearings.
Distances extracted from the field file are reduced for slope to a horizontal distance which is passed to the traverse file. You have the option of applying mean sea level and line scale factor where appropriate as part of the adjustment process when the traverse file is adjusted using the traverse file editor Solve menu. Refer to the Solve/Corrections command.
Height differences extracted directly from the field file are passed to the traverse file unchanged. However, height differences will also be computed if a traverse observation contains a slope and slope distance. These computed height differences can be corrected for earth curvature and refraction before being passed to the traverse file.