Sample Survey Point Files with Expected Results

Use examples as checks, not as project defaults

A useful sample does more than demonstrate a button. It gives you an input, a stated interpretation and an expected result that you can compare with the actual output. The files on this page are deliberately small so you can inspect every row. Their point numbers, coordinates and heights were created for demonstration. Do not copy their reference, units, tolerances or design assumptions into a real job merely because an example produces a successful report.

The point tables share a documented PNEZD layout with a header: Point, Northing, Easting, Elevation and Description. Their horizontal and vertical units are metres in a synthetic local reference. The Open in checker link loads the selected named file, not an unrelated generic sample. It still leaves interpretation confirmation to you. Downloading the source is another option, especially when you want to inspect its raw text or compare the result in a second application.

Begin with the clean four-point rectangle

The clean table contains four identifiers with leading zeroes and four known elevations. Interpreted correctly, the points trace a rectangle thirty metres wide and twenty metres high in plan. All four records should be processable without a blocked coordinate. Plot them to verify that the corners appear in the expected order. Check the actual Easting and Northing values as well as the outline: a rectangle can still look convincing after an incorrect axis interpretation.

Use this file in the area tool by choosing the original four records in source order. The expected planar area is six hundred square metres and the perimeter one hundred metres. These are plan quantities, not surface area. A converter exercise can exchange the Northing and Easting columns to produce PENZD while preserving each point's interpreted position. Reimport that output with its new mapping and compare all four records, including the leading-zero identifiers and descriptions.

Examine a file that is supposed to contain problems

The issues table intentionally retains five records. One row has no Northing, another has a nonnumeric Northing, and point identifier 001 occurs twice. Point 004 has an unknown elevation. With the documented mapping and optional height interpretation, two records have blocked coordinates; the repeated identifier needs review, and the unknown height must remain blank. The purpose is to inspect the reasons, not to force all five rows into an apparently clean output.

Try correcting a copy of one known error and run the check again. An empty value should only be replaced when a legitimate source provides it; for a teaching exercise, label any invented replacement as synthetic. Keep the original file so you can compare what changed. This is also a useful cancellation and restoration exercise: clear the current session, reload the same source, confirm the mapping and verify that every original problem is present again.

Compare design and measured data at a tolerance boundary

The design and measured tables each contain four records. A, B and C have counterparts; each side also contains one unmatched identifier. At A, the measured-minus-design components are 0.03 metres east, 0.04 metres north and 0.01 metres in height. The horizontal magnitude is 0.05 metres. With horizontal and vertical tolerances of 0.05 and 0.01 metres, respectively, A is within both inclusive boundaries.

At B, the Easting difference is 0.08 metres and the height difference is minus 0.02 metres, so the point exceeds the supplied tolerances. At C, the plan coordinates agree but the design elevation is missing; the result is partial, not a full pass. The unmatched records must remain visible. These cases let you distinguish a signed component, a horizontal magnitude, an inclusive boundary and an unassessable quantity without relying on an actual construction acceptance standard.

Separate a revised file from a measured comparison

The revision table is based on the clean rectangle table, but it is not a set of field observations. Identifiers 001 and 004 are unchanged, 002 has an Easting increase of 0.1 metres, 003 is absent and 005 is new. The row order is also different. A revision comparison should therefore identify unchanged, modified, removed and added records without treating a reordered row as a movement on its own.

This exercise illustrates why keeping both sources matters. If you overwrite the old file first, you lose the basis for demonstrating which point was removed and what the old coordinate of 002 was. Download the full change list and inspect the point values rather than only the summary count. If a future project deliberately renames points between versions, correspondence needs another explicit basis; the matching behavior of this small example should not be generalized to ambiguous real identifiers.

Review an original TIN before querying it

The LandXML sample contains a point group and a separate surface made from two original triangles. Select the surface rather than the point group when you want heights or terrain sections. Its plane is defined by Z = 100 + 0.1 E + 0.2 N, with metre units. The square surface covers Easting and Northing from zero to ten. At E5, N5 the expected height is 101.5, including the shared triangle edge.

A query outside the square must not receive an invented extrapolated elevation. A longitudinal section through the surface should retain the original face crossing even though both triangles happen to lie on one plane. The sample is intentionally simpler than an engineering terrain mesh; it teaches object selection, axis order, units and coverage. It does not exercise every hole, overlapping triangle, invalid reference or boundary condition handled by the larger regression suite.

Reduce the observation example with explicit angle settings

The three-row observation file uses zenith angles in decimal degrees, metre distances and metre heights. A slope distance of one hundred at a zenith angle of ninety has horizontal distance one hundred and vertical instrument-to-target component zero. With instrument height 1.5, target height 2 and station elevation one hundred, the calculated target-ground elevation is 99.5. Keeping these separate quantities visible makes the sign of the height corrections easier to review.

The other rows use zenith angles sixty and one hundred twenty. One row intentionally lacks a station elevation, so relative quantities can be available without an absolute target elevation. Do not select vertical-angle or compact-DMS mode for this file. Those settings describe different input meanings. The worksheet and text examples demonstrate the file workflow; they do not supply prism corrections, meteorological parameters or an instrument calibration certificate.

Keep a record of what you checked

For each exercise, save the source filename, mapping, units, selected method, expected result and actual result. Include every unexpected or uncomputed row rather than only successful outputs. If you report a discrepancy, refer to the example filename and row so another person can reproduce it without receiving confidential project coordinates. A small named fixture is more useful for diagnosis than an unexplained screenshot of a large private dataset.

When moving to your own file, replace every teaching assumption with documented project information. Inspect a known control and a small output in the receiving software before relying on a full batch. Closing or reloading a page is not a backup strategy; download the reports you need. The examples are provided to help understand scope, errors and handoffs, while actual survey acceptance remains dependent on the appropriate source evidence, methods and professional review.

Questions and answers