To Define a Survey Centerline

To define a centerline, you specify a figure name, starting station, and starting point number.

If you use a point off the centerline to determine the beginning station, then a perpendicular line is established and that intersection is the starting station. Therefore, any point you use to establish the beginning station must be adjacent to some leg of the centerline.

To define a centerline from the Survey Command Window menu

1. In Toolspace, on the Survey tab, right-click the network to edit, and click Survey Command Window.
2. Click Centerline menu Define Figure Centerline.
3. Enter a figure name for the centerline.
4. Enter the starting station value.
5. Enter the starting station point identifier. This is the location to start stationing from. The starting station is the perpendicular intersection of the starting station point identifier and the centerline.

To define a centerline, using the survey command language

1. In Toolspace, on the Survey tab, right-click the network to edit, and click Survey Command Window.
2. At the Command line, enter:

   CL IS [figure] (station) (point)

Command Line Example

In the following example, the beginning of this command sequence describes how to draw the centerline figure.

BEGIN CL1

NE 1 1000 1000

NE 2 1000 1500

NE 3 1300 1700

END

NE 4 1100 1100

CL IS CL1 500 4

! Figure CL1 is the current centerline.

! Start Station: 400.00 End Station: 1260.56

Figure CL1 is the current centerline. Assigning Point 4 a station of 5+00 results in the centerline starting at station 4+00.

Centerline figure

Command Syntax

CL IS [figure] (station) (point)

Parameter	Definition
figure	The figure that you want to use as the centerline.
station	The defining station of the centerline. If you do not type a point number, then this is the station at the beginning of the figure. If you type a point number, then the station is at the point you specify. When you don't specify a station, the default 0+00 is used.
point	An optional reference point for the station. The point specified need not be on the centerline, but it must be adjacent to the centerline (not beyond the end points).