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Percent volume contours
Note that a percent volume contour is not the same as the simple contours that are typically produced in tools like Spatial Analyst. A percent
volume contour represents the boundary of the area that contains x% of the volume of a probability density distribution. A simple
contour (like the ones that are produced in Spatial Analyst) represent only the boundary of a specific value of the raster data, and does not
in any way relate to probability. For applications like animal home range delineation it is the percent volume contour that is required. The 95%
volume contour would therefore on average contain 95% of the points that were used to generate the kernel density estimate.
Getting started
You MUST ensure that you have a Spatial Analyst or 3D Analyst available before you start this tool (in ArcMap, see Tools > Extensions,
and ensure there is a check-mark next to one of these extensions). A raster layer must be loaded into ArcMap in order to use this tool.
The raster layer should represent a probability density surface, like a kernel density estimate.
Output folder
Because this tool can generate many different output layers, the user is asked to specify an output folder (preferably a new, empty folder)
so that the tool can automatically generate the output shapefiles. An empty folder will ensure that the program does not encounter naming
conflicts with pre-existing shapefiles.
Naming convention
The names of the shapefiles produces (one for each % value supplied) will be: PVC + the name of the raster + the percentage value.
Percent contour values
You may enter any number of percent contour values as a comma delimited list, e.g.: 10, 20, 30, 90, 40, 75.68
Note that the numbers do not have to be ordered, and decimals are allowed.
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