2.15 Control coordinates

Control (known) coordinates are described by the start-end pair tag <coordinates>. A series of points with known coordinates can be defined using the <point /> tag. The variance-covariance matrix for the entire set of points can be created with a single <cov-mat> tag. In the <point /> tags, a point identification (ID) and its coordinates (x, y and z) must be listed. Although the order of the <point /> tag attributes is irrelevant in the corresponding variance-covariance matrix, the expected order of the coordinates is x, y and z (the horizontal coordinates x, y, or the height z might be missing, but not both). The type of the points may be defined either directly within the <coordinates> tag or outside of it.

Example

     <coordinates>
        <point id="1" x="100.00" y="100.00" />
        <point id="2" z="200.00" y="200.00" x="200.00" />
        <point id="3" z="300.00" />
        <cov-mat dim="6" band="5" >
            ...  <!-- covariances for 1x 1y 2x 2y 2z 3z -->
        </cov-mat>
     </coordinates>