Automatic generation of elevation data over Danish landscape

6 Pre-analysis of the generated data
even with a small number of interest points (a), and areas where the generation is not done, in spite of
the existence of a sufficient number of interest points, for instance area (d), and in particular area (e).
Other results from graphic online functions indicate that some of the calculations are perhaps not finished,
but have stopped midway, cf. figure 6.2. It must be emphasised here that figure 6.2 is not a screen dump
in the middle of the calculation, but the last image!
Figure 6.2: The result of the online function for the model 161162 with the resolution 30 μm
and mesh size 12.5 x 12.5 m.
These examples create the suspicion that the generated grids are not always uniform, or that the calculation
has stopped in mid-course. If the examples shown are representative of the quality and uniformity of
the grids generated automatically by Match-T, there is cause for deep concern.
This leads to an investigation into the uniformity and completeness of the grid files. The files must have
the same size, when the same scale and mesh size are used. For example, the files with scale 1:25,000,
resolution 15 μm and mesh size 25 x 25m must have the same size as the files with scale 1:25,000, resolution
30 μm and 60 μm and mesh size 25 x 25 m, as they include the same number of grid points. By
comparing the size of the files, it is discovered that those files which were expected to be of equal size,
are not necessarily so. Table 6.2 shows the file sizes for scale 1:25,000.
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