COLUMBUS provides several tools for examining your field data and finding blunders. Our powerful open and loop traverse closure tools quickly allow you to check closures. Just point and click to lay out a traverse, then select either the 1D, 2D or 3D traverse option. Coordinates along the traverse, as well as closures, are immediately computed and displayed.

After performing a network adjustment, COLUMBUS provides you with three distinct outlier detection tests.

standardized residual

The second test compares each adjusted observation residual against its expected error (a priori standard deviation used to weight the observation).

The third test compares each observation residual against a pre-selected maximum. Each observation type (azimuth, zenith angle, etc.) can have a different pre-selected maximum cutoff value.

Each test can be performed repeatedly with different critical values without re-adjusting.

Any column of data can be sorted to show the largest/smallest values from the adjustment.

Additionally, COLUMBUS automatically searches for no-check (or side-shot) observations (observations that received no adjustment). These often indicate that one or more stations are "flylined" off the main network.

Finally, GPS XYZ residuals can be expressed in Local North, East, Up form. This is extremely useful when looking for instrument centering and height measurement errors common to GPS networks.

Back to Top

Network Adjustment and Coordinate Transformation
Software Solutions • Since 1990