This command processes a group of
points to compute the best fitting centerline by least squares. The
points can be input from Carlson points or from vertices of a
polyline. For points input, the points can be selected by screen
selection or point number range. Each line segment in the
centerline is calculated by the best-fit line method and each arc
segment is calculated by the best-fit arc method. The line and arc
segments are then made to be tangential.
In the process options dialog, the
Snap Tolerance is the max offset from the point to the line or arc
segment in order to be counted as part of that segment. The Max
Radius controls the maximum radius for arc segments that the
program will fit to the data. The Create Tangents Only option skips
the step of calculating the best-fit arcs and outputs only the
lines. Arcs can be added later using routines like Fit Curve in the
Input-Edit Centerline command.
The
residual for each point is the perpendicular distance from the
point to the best-fit centerline. The results are shown in a dialog
and you can toggle each point for whether to include in the
calculations. Points that are toggled off are not used for
calculating the centerline but are still used in the residual
report. The Remove function removes the point from both calculation
and residual reporting.
PromptsInput existing data from points or polyline
[<Points>/Line]? press Enter
Select points from screen or by point number
[<Screen>/Number]? S
Select Carlson Software Points.
Select objects: pick the centerline points
Pulldown Menu Location: COGO
Keyboard Command: bestcl
Prerequisite: Group of
points or a polyline to sample