fsr (version 1.0.0)

spa_support: Capturing the support of a pgeometry object

Description

This function yields a crisp spatial object (as an sfg object) that corresponds to the support of a pgeometry object given as input.

Usage

spa_support(pgo)

Arguments

pgo

A pgeometry object of any type.

Value

An sfg object that represents the support of pgeometry. It can be an empty object if pgeometry is empty.

Details

It employs the classical definition of support from the fuzzy set theory in the context of spatial plateau algebra. The support only comprises the points with membership degree greater than or equal to 1. Hence, this operation returns the sfg object that represents the total extent of the pgeometry given as input. If the pgeometry object has no components, then an empty sfg object is returned (i.e., a crisp spatial object without points).

References

Carniel, A. C.; Schneider, M. A Conceptual Model of Fuzzy Topological Relationships for Fuzzy Regions. In Proceedings of the 2016 IEEE International Conference on Fuzzy Systems (FUZZ-IEEE 2016), pp. 2271-2278, 2016.

Examples

# NOT RUN {
library(sf)

pts1 <- rbind(c(1, 2), c(3, 2))
pts2 <- rbind(c(1, 1), c(2, 3), c(2, 1))
pts3 <- rbind(c(2, 2), c(3, 3))

cp1 <- component_from_sfg(st_multipoint(pts1), 0.3)
cp2 <- component_from_sfg(st_multipoint(pts2), 0.6)
cp3 <- component_from_sfg(st_multipoint(pts3), 1.0)

pp <- create_pgeometry(list(cp1, cp2, cp3), "PLATEAUPOINT")
pp

pp_supp <- spa_support(pp)
pp_supp

pp_empty <- create_empty_pgeometry("PLATEAUPOINT")
pp_empty_supp <- spa_support(pp_empty)
pp_empty_supp

# }