Least-squares adjustment errors and their descriptions

This topic applies to ArcGIS for Desktop Standard and ArcGIS for Desktop Advanced only.

After a least-squares adjustment has completed, an adjustment summary of the results is displayed. If the adjustment failed to complete, the adjustment summary will state ADJUSTMENT FAILED and will list the reasons why the adjustment failed. If the adjustment completes successfully, the adjustment report will state ADJUSTMENT COMPLETED.

If the adjustment completes successfully, the maximum coordinate shift resulting from the adjustment is displayed under the Help button under Maximum shift. If you scroll down in the adjustment summary, the point that received the maximum coordinate shift is listed with the average coordinate shift for all points.

A fabric least-squares adjustment should be run repeatedly (iteratively) until the maximum and average coordinate shifts become 0.0 or very small. To iterate the adjustment, click Accept on the Least Squares Adjustment Summary dialog box and then click Run again on the Adjust Coordinates dialog box. To complete the adjustment, click OK on the Adjust Coordinates dialog box.

Errors causing the adjustment to fail

The following list describes adjustment failure errors and their resolutions:

• ERROR: Unable to complete adjustment. You are trying to adjust too many parcels. The upper limit of parcels that can be adjusted is 5000. Add more control or reduce the number of parcels being adjusted.

  There is a limit to the number of parcels the least-squares adjustment can handle. To resolve this error, reduce the number of parcels you are trying to adjust.

• ERROR: Unable to complete adjustment. There are not enough system resources.

  You may not have sufficient computer resources to run this adjustment. Try closing any existing applications that may be using up system resources.

• Unable to preprocess adjustment: Make sure blocks of parcels in the adjustment are connected, for example, at road intersections.

  This error usually occurs with other errors. The most common cause of this error is a poorly connected parcel network. To resolve this error, improve the connectivity of the network and merge close or overlapping points.

• Unable to complete adjustment. There is not enough control to adjust this many parcels.

  Ideally, control points should be well distributed in a group of parcels that is being adjusted. When adjusting a large number of parcels, you should have a sufficient number of control points. Minimal control does not produce reliable results. Add more control points to resolve this error.

• ERROR: Unable to complete adjustment. <number> parcel lines did not adjust within 3x the specified tolerances.

  Parcel lines that have a bearing or a distance that adjusts more than three times the specified tolerances will cause the adjustment to fail. These lines are marked with a ## in the Parcel Lines report. Either increase your check tolerances or investigate the problematic lines if the c-o (computed minus observed) values are large. The computed line is the line that is computed from the adjusted coordinates, and the observed line is the original line derived from the existing dimensions on the line.

• ERROR: Unable to complete adjustment.<referenced line> has an invalid distance

  The distance attribute of this line is invalid. To resolve this error, open the parcel that uses this boundary line and correct the distance value of the line in the parcel traverse grid.

• ERROR: Unable to complete adjustment. <referenced line> has end points with the same coordinates

  This error is self-explanatory. To resolve the error, open the parcel that uses this line and reenter the line in the parcel traverse grid.

• ERROR: Unable to complete adjustment. There are insufficient points.

  Possible reasons:

  1. The network is too small; at least three parcels are required.
  2. A large number of lines were excluded from the adjustment because the accuracy category was set to category 7. Unable to preprocess adjustment: Make sure blocks of parcels in the adjustment are connected, for example, at road intersections.

  This error is self-explanatory. Note that if you set the accuracy category of a line to 7, it is excluded from influencing the outcome of the adjustment, but the line will still receive the resulting adjustments.

• ERROR: Unable to complete adjustment. To solve the problem, resolve these warning messages, and merge any reported close points. Cause: Network error at point number <PointID>. Check observations/bearings around the point. Aborting adjustment.

  Unable to preprocess adjustment: Make sure blocks of parcels in the adjustment are connected, for example, at road intersections.

  To resolve this error, investigate parcel lines connected to this point. Check for close or overlapping points and poor connectivity around the area.

• ERROR: Unable to complete adjustment. The network lacks connectivity. Make sure blocks of parcels in the adjustment are connected, for example, at road intersections. One or more points may be poorly connected or unconnected. Check network connectivity or add control. Unable to preprocess adjustment: Make sure blocks of parcels in the adjustment are connected, for example, at road intersections.

  The most common cause of this error is a poorly connected parcel network. To resolve this error, improve the connectivity of the network and merge close or overlapping points.

• ERROR: Unable to complete adjustment. The network lacks connectivity. Make sure blocks of parcels in the adjustment are connected, for example, at road intersections. Connectivity error at or near point ID <point ID>. One or more points may be poorly connected or unconnected. Check network connectivity or add control. Unable to preprocess adjustment: Make sure blocks of parcels in the adjustment are connected, for example, at road intersections.

  To resolve this error, check for connectivity problems around the referenced Point ID.

• ERROR: Unable to complete adjustment: <referenced line> Line end points <points> are too close. Distance = <number>. Check if points should be merged.

  These points are most likely the same point. The line should be deleted from the traverse grid and the points should be merged. If this line is supposed to be small, check to make sure that there are bearing and distance values in the line attributes.

• ERROR: Unable to complete adjustment. Check if there is sufficient connectivity in your network. Unable to preprocess adjustment: Make sure blocks of parcels in the adjustment are connected, for example, at road intersections.

  The most common cause of this error is a poorly connected parcel network. To resolve this error, improve the connectivity of the network and merge close or overlapping points.

• ERROR: Unable to complete adjustment. Too many close points <number> have been found. Only <number> allowed. Use the Merge points tool to merge duplicate points.

  Close points are those points that are close enough to each other to be the same point. Close points or overlapping points compromise the connectivity of the network and should be merged.

• Unable to complete adjustment: Close Points <points> could not be referenced.

  This error is not common. Check the validity of the referenced points and merge any close points or overlapping points.