To What Elevation are Measurements Assigned Cross-section and 3D Contours?

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To What Elevation are Measurements Assigned Cross-section and 3D Contours?

For cross-section and 3D contours where the measurements are specified over relatively long sample intervals, EnviroInsite can interpret these measurements as more than a single point measurement at the vertical center of the sample interval. The work of assigning points occurs prior to the interpolation onto the contour grid. The relevant controls in the contour dialog box Options tab are Points per Sample Interval and Minimum # Points.

 

If the Points per Sample Interval is set to 2, then there will be at least two measurement points applied along the interval. For example, a 2-foot sample interval between 4 and 6 feet deep will initially be treated as measurement points occurring at depths of 4.5 feet and 5.5 feet. That is, the program divides the physical interval into sub-intervals equal to the minimum number of points and places a measurement point at the center of each interval.  

 

Next, EnviroInsite compares the specified Maximum Interval Height Per Point to the length of the sub-intervals calculated initially based on the specified Minimum # Points. If the sub-interval lengths exceed the Maximum Interval Height Per Point, then the program will reallocate the measurement points based on the Maximum Interval Height. Consider the previous example of an interval extending from 4 to 6 feet with the Minimum # Points set to 2. If the Maximum Interval Height is set to 0.5 feet, then the sub-interval length (equal to 1) exceeds this value and the measurement points are setup based on four intervals of 0.5 feet, with the measurement point at the center of each interval. That will result in measurement points at depths of 4.25, 4.75, 5.25, and 5.75 feet.