# Duplicate point tolerance options

The duplicate point tolerance options in the survey style determine what happens if you attempt to store a point with the same name as an existing point, or if you measure a point that is very close to an existing point that has a different name.

When configuring these settings, make sure you are familiar with the database search rules applied by the software when managing points of the same name. See Managing points with duplicate names.

Same point name options

In the Same point name group, enter the maximum horizontal and vertical distances or angles that a new point can be from an existing point of the same name. A duplicate point warning appears only if the new point is outside the tolerance set. To always receive a warning if you measure a point with the same name, enter zero.

Auto average tolerance

To automatically compute and store the average position of points that have the same name, select the Auto average within tolerance option. An averaged position has a higher search class than a normal observation.

When the Auto average option is selected, and an observation to a duplicate point is within the specified duplicate point tolerance settings, the observation and the computed average position (using all the available point positions of the same name) are stored.

You can select the averaging method in the Cogo settings screen.

The Trimble Access software computes an averaged coordinate by averaging the grid coordinates computed from the underlying coordinates or observations. Observations that do not allow a grid coordinate to be resolved (for example, angles only observations) are not included in the average coordinate.

If the new point is further from the original point than the tolerance specified, you can choose what to do with the new point when you store it. The options are:

- Discard – discard the observation without storing.
- Rename – rename to a different point name.
- Overwrite – Overwrite and delete the original point, and all other points of the same name and the same (or lower) search class.
- Store as check – Store with a lower classification.
- Store and reorient – (This option only appears if you are observing a backsight point.) Store another observation that will provide a new orientation for subsequent points measured in the current station setup. Previous observations are not changed.

- Store another – Store the point, which can then be averaged in the office software. The original point is used in preference to this point.

  If the Store another option is used with multiple observations to a point with the same name and from the same station setup, then when measuring topo points the software automatically computes and records a Mean Turned Angle (MTA) observation to the point. This MTA observation provides the preferential position for the point.

- Average – Store the point and then compute and store the averaged position.

  When you select Average, the current observation is stored and the computed average position appears, along with the computed standard deviations for the north, east, and elevation ordinates. If there are more than two positions for the point, a Details softkey appears. Tap Details to view the residuals from the average position to each individual position. You can use the Residuals form to include or exclude specific positions from the average computation.

Face 1 and face 2 observation tolerance

In a conventional survey, when you attempt to measure a point on face 2 that already exists as a face 1 measurement, the software does not warn that the point already exists.

When you carry out two‑face observations in a conventional survey during Station setup, Station Setup Plus, Resection, or when measuring Rounds, the software checks that the face 1 and the face 2 observations to a point are within a preset tolerance.

If the new point is further from the original point than the tolerance specified, you can choose what to do with the new point when you store it. The options are:

- Discard – discard the observation without storing.
- Rename – rename to a different point name.
- Overwrite – Overwrite and delete the original point, and all other points of the same name and the same (or lower) search class.
- Store as check – store with a classification of Check.
- Store another – store the observation.

Once you have completed the Station Setup Plus, Resection, or Round measurements, the software saves the Mean Turned Angles to each of the observed points. The software does not check for duplicate points at this stage.

Different point name options

To enable proximity check for points with different names, enable the Proximity check switch. Enter the horizontal and vertical distance that the new point can be from any existing point.

- The vertical tolerance is only applied when the new observed point is within the horizontal tolerance. Use the vertical tolerance to avoid the proximity check warning when new points are measured above or below existing points but are legitimately at a different elevation, for example the top and bottom of a vertical curb.
- The proximity check is only performed on observations, not on keyed in points. The proximity check is not performed in stakeout, GNSS Continuous measurement, or Calibration Point, and it is not performed in jobs with a No Projection coordinate system.