Difference Points

Calculates elevation difference between points and a surface with an optional reference to an alignment. Results can be added as Point UDP on the existing point, or new points created at the difference value.

Keyboard Command: PntAddDif

Section Details:

Parameters:

• Source Group: Select the existing point group to process or use the < button to select points.
• Compare Surface: Select the defined surface to calculate the vertical difference.
• Reference Alignment: An existing alignment to use for calculating station and offset values.
• Calc Vert Using: You can calculate the number based on surface elevation minus point elevation, or vice-versa.

Output Options:

• Add Properties:
  • Difference: The field name to use for the difference value in the extended dats (or UDP).
  • Elevation: The field name to use for the elevation value in the extended dats (or UDP).
• Create Points:
  • Description: You can enter a description for the point or use the default tag <PntDes>. With this default the point description will vary, being that of the original designated point.
  • Group: Designate the point group to use for creating the difference points. Its highly recommended that you use a new group!

Procedure:

1. Initiate the tool from the menu, ribbon, or command above.
2. Enter the number range or choose an adjacent button to build the string.
3. Choose a surface to compare against.
4. Optionally choose an existing alignment.
5. Choose the Process button to build the list.
6. Designate any additional options desired.
7. Choose a different point group or enter a new name.
8. Choose the OK button to create the points.

Notes:

• If an alignment is selected, the grid will include columns for station and offset. If no alignment is selected (none) then these columns will be absent.