MarkLogic 12 EA 1 Product Documentation
geo:count-distinct-verticesgeo:count-distinct-vertices(
$region as cts:region,
[$options as xs:string*]
) as xs:integer
Summary
Return a count of the distinct number of vertices in a region, taking
tolerance into account.
Parameters |
region |
A cts region.
|
options |
Options include:
- "coordinate-system=value"
- Use the given coordinate system. Valid values are
wgs84 , wgs84/double , etrs89 ,
etrs89/double , raw
and raw/double . Defaults to the governing coordinating
system.
- "precision=value"
- Use the coordinate system at the given precision. Allowed values:
float and double . Defaults to the precision
of the governing coordinate system.
- "units=value"
- Measure distance, radii of circles, and tolerance in the
specified units. Allowed values:
miles (default),
km , feet , meters .
- "tolerance=distance"
- Tolerance is the largest allowable variation in geometry calculations.
If the distance between two points is less than tolerance, then the two
points are considered equal. For the raw coordinate system, use the units
of the coordinates. For geographic coordinate systems, use the units
specified by the units option.
|
Usage Notes
This function returns a count of the distinct number of vertices in a
region. It takes into account tolerance. The vertex that closes the ring
is only counted once. For a complex polygon this is a count of the vertices
in the outer polygon. For points it returns 1, for circles it returns 0,
and for boxes it returns the number of distinct points in the set
(sw, se, nw, ne).
The value of the precision
option takes precedence over
that implied by the governing coordinate system name, including the
value of the coordinate-system
option. For example, if the
governing coordinate system is "wgs84/double" and the precision
option is "float", then the operation uses single precision.
See Also
Example
geo:count-distinct-vertices(
cts:polygon((cts:point(1,2),cts:point(3,4),cts:point(3,4),cts:point(4,5),
cts:point(1,2))) )
=> 3
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