calcMidRange {PBSmapping}R Documentation

Calculate the Midpoint of the X/Y Ranges of Polygons

Description

Calculates the midpoint of the X/Y ranges of polygons found in a PolySet.

Usage

calcMidRange (polys, rollup = 3)

Arguments

polys PolySet to use.
rollup level of detail in the results; 1 = PIDs only, 2 = outer contours only, and 3 = no roll-up.

Details

If rollup equals 1, the results contain a mean range for each unique PID only. When it equals 2, they contain entries for outer contours only. Finally, setting it to 3 prevents roll-up, and they contain a mean range for each unique (PID, SID).

Value

PolyData with columns PID, SID (may be missing), X, and Y.

See Also

calcArea, calcCentroid, calcLength, calcSummary.

Examples

#--- load the data (if using R)
if (!is.null(version$language) && (version$language == "R"))
  data(nepacLL)
#--- calculate and print the centroids for several polygons
print(calcMidRange(nepacLL[is.element(nepacLL$PID, c(33, 39, 47)), ]))
[Package PBSmapping version 2.09 Index]