#### Determining the Data Used to Construct the Arc

The data used to construct the arc is determined as follows:

- First, a segment of the scan is determined using a starting point and an ending point within the scan. The starting and ending points are chosen as the point in the scan nearest [start_x, start_y, start_z] and the point nearest [end_x, end_y, end_z] respectively.

- Points are then discarded from the start and end points of the scan. The number of points discarded from the start is discard_start and from the end is discard_end. An arc is then fitted to this set of points.

- Finally, the starting and ending points are added back in if they are within the defined tolerance. The arc is then re-fitted once more to the new set of points.

The value of fit_type may be BF (Best Fit) or BFRE (Best Fit Recompensate). This determines whether a best fit or best fit with recompensation is done when calculating the arc. For a description of Best Fit and Best Fit Recompensate, see "Constructing a Best Fit or Best Fit Recompensate Circle".