Usage
intersectPolyCircle(object, center, radius, ...)# S3 method for owin
intersectPolyCircle(object, center, radius, npoly = 32, ...)
# S3 method for SpatialPolygons
intersectPolyCircle(object, center, radius, npoly = 32, ...)
# S3 method for gpc.poly
intersectPolyCircle(object, center, radius, npoly = 32,
useGEOS = FALSE, ...)