Reporting by elevation
There are three functions that allow reporting by elevation : DTM Cut and Fill Volumes, DTM Volumes, and the Object Report function. Reporting by elevation allows a number of elevation intervals to be defined for reporting purposes. An elevation interval is a region that is bounded by an upper and lower Z value. While standard Surpac ranges are used to define elevation intervals, extra validation occurs on these ranges to ensure that the elevation intervals defined are valid. Valid ranges must include at least two values and be strictly increasing, or strictly decreasing.
Reporting by elevation allows data that would normally be presented as a total to be examined at specific intervals. For example, using Report by elevation in the Object Report function would allow reporting of the volume and surface area of an object at specified Z intervals.
Valid elevation range
The following ranges would be considered valid for the purposes of reporting by elevation:
Range:1,2
Range:1,20,21
Invalid elevation range
The following ranges would be considered invalid for the purposes of reporting by elevation:
Range :1. This is invalid because there is only one value in the range.
Range :1;100;10,5.
This is invalid because the range initially increases before decreasing.
Range :1;100;10,5.
This is invalid because the range does not strictly increase.
Elevation range interpretation
It is important to note that a particular elevation interval does not include the upper limit Z value.
For example, given the range 1;2;3, the following elevation intervals would be defined:
Elevation interval 1: 1<=Z<2
Elevation interval 2: 2<=Z<3
Report Warnings
It is possible that the elevation intervals defined do not encompass the Z extents of the object/DTM or even include any part of the object/DTM at all. Under these conditions, the report will include the appropriate warning.