Resection - MDT25

25.23 Resection

This option allows one to calculate stations that have target at least three known coordinate points. Its use is very similar to the Direct Intersection command. It can be accessed through the Surveying > Utilities > Inverse Intersection drop-down menu or by clicking the Resection button from the Station Calculation screen. In the former case, it requests an occupation point to be selected:

Combinations are calculated three by three with this method, automatically deleting the badly conditioned ones that lead to the "Dangerous Circle" case.

If the Goodness-of-fit tests have been activated under the Least Squares option within the topography configuration, the Results frame will be shown if the Chi-Square test has been passed or not. Furthermore, in the lists of distance, azimuth, angular and vertical observations, a column is added with the reliability level resulting from the Baarda Test. In this case the values may be: perfect, good, poor, bad or incorrect.

Furthermore, the results also include the Horizontal Correction which will be assigned automatically to the positioning used. The results have the same structure in sections with the following format:

INVERSE INTERSECTION CONTROL STATIONS

Element X Coord. Y Coord. Z Coord. Ang. Error Dist. Error Height Error

E 5 299989.317 4000035.758 100.746 0.0000 0.013 -0.002

E 2 299949.759 4000031.202 97.563 -0.0000 0.025 -0.000

E 11 299896.356 4000099.534 94.348 0.0147 -0.040 -0.004

E 10 299847.406 4000119.451 92.684 -0.0129 -0.006 0.007

RESULTS

Planimetric Adjustment

Calculation by Angles and Distances

Solve: X: 299962.795 Y: 4000056.828 CH: 142.7377

Standard Deviation: X: 0.0033 Y: 0.0037

Ellipse Error: Su: 0.0109 Sv: 0.0085 Orientation: 366.3611

Square Chi Test

Degrees of Freedom: 12 Chi2: 5.1046e-005

Confidence Level: 95 % Passed

Altimetric Adjustment

Solve: Z: 97.747

Standard Deviation: Z: 0.0025