Quick Tips for Using COLUMBUS

Inverse

• Calculating inverses from the main view and from the adjusted network view
  
  
• Calculating the inverse between two geodetic stations

Calculating inverses from the main view and from the adjusted network view

Please see the related topic, Calculating the inverse between two geodetic stations, for using the mouse to select an inverse route.

From the Main Project View

You can calculate inverses based on the current station data in memory by interacting with the main project view. This is the view that is displayed when you either load an existing COLUMBUS data file or enter data by selecting Stations from the Data menu and using the data management grids.

For a 3D Geodetic type inverse (with 3D Geodetic view active), the geodetic station fields used will be latitude, longitude and one of the height fields. The height field used is determined by the 3D Geodetic Height setting in the Options | Global Settings dialog box (either the orthometric height field or the ellipsoidal height field). When calculating the 3D Astro Geodetic Inverse, the deflections of the vertical fields will also be used from each geodetic station (if provided).

For a 2D Mean Bearing type inverse (with 2D Geodetic view active), the geodetic fields used will be the latitude, longitude and the 2D Height setting in the same dialog.

From the Adjusted Network View

You can also calculate inverses from the Results | Adjusted Network View. When this view is used, the inverses are based on the current adjusted station data. For a 3D Geodetic adjustment based on ellipsoidal height, the inverse will be based on the adjusted latitude, longitude, and ellipsoidal height at each station. If the adjustment is based on orthometric height, the inverse will be based on latitude, longitude and orthometric height.

Note: When a 2D Geodetic Inverse is calculated, the height component is always Zero (on the surface of the reference ellipsoid), regardless of whether you are working from the Main Project View or the Adjusted Network View.

Back to top

Calculating the inverse between two geodetic stations

To calculate an inverse between two geodetic stations, do the following:

1. Run COLUMBUS.

2. From the File menu, select New.

3. From the Options menu, select Datums and select the datum to be active.

4. From the Data menu, select Stations.

5. Select the Geodetic dialog tab and enter the geodetic coordinates for each station.

6. Click Keep and Exit.

7. Right click on the AT station, then right click on the TO station. A line will appear between them.

8. From the Tools menu, select COGO and then select the desired inverse option to calculate the applicable inverse (or toolbar button).