classNeighborFunction: Calculation of relations from a class to its neighbor objects

In ggRaver/Lslide: Functions for object-oriented image analysis in landslide science

Calculation of relations from a class to its neighbor objects

Description

This function calculates statistics for every object of a specific class to its neighbor objects. It is computationally identical to the relationalObjectFunction. However, the function additionally enables the possibility to perform statistics for neighbors in a specific direction, likewise the relationalClassFunction, and to select class objects by expressions.

Usage

classNeighborFunction(spdf, nb, class.var, var, calc.nb.flow = FALSE,
  col.flow = NULL, bb.intersection = "rgeos",
  class.as.neighbors = FALSE, bb = NULL, return.bb.flow = FALSE,
  scale.factor.flow = c(1, 1), centroid.flow = TRUE,
  set.centroid.flow = "inverse", k.centroid.flow = 2, k.flow = 2,
  scale.side.flow = "small", quiet = TRUE)

Arguments

spdf	SpatialPolygonsDataFrame, or full path of a shapefile
nb	object neighborhood based on poly2nb. Otherwise, neighborhood is computed by spdep::poly2nb(..., Queens = TRUE)
class.var	defination of class. Can be string or integer, or an expression in form of a list. For examples: class = as.integer(1), class = list("> 2.5", "expression"), class = list(c("> 2", "&", "< 7"), "expression")
var	vector with number or name defining 1. field of evaluation (i.e. slope) and 2. field of weights (i.e. area). For example: c("Slope", "Area") or c(1,2)
calc.nb.flow	include statistics for neighbors in flow direction. Default: FALSE
col.flow	column specifying direction. Default: NULL
bb.intersection	method for intersection with bounding box. Default: "rgeos" (alternative: "sp")
class.as.neighbors	class object is also neighbor object. Default: FALSE
bb	input of bounding box geometry. Default: NULL
return.bb.flow	return geoemtry of counding box. Default: FALSE
quiet	no outputs in console. Default: TRUE
only.neighbors	object statistics are computed only for neighbors. Default: TRUE (FALSE means computation for the entiry data)
other...	see getBoundingBox

Value

data.frame containing object statistics, and optional the created geometry of getBoundingBox

Note

• class statistics to neighbor objects acccording to ECOGNITION DEVELOPER (2014: 253-255, 375-381):

  • see relationalObjectFunction

  • ~_nb_FlAl - statistics for all objects located in flow direction

  • ~_nb_FlMa - statistics for direct neighbors located in flow direction

• ECOGNITION DEVELOPER (2014) Reference Book. Trimble Documentation, München, Germany

• see getBoundingBox

• SpatialPolygonsDataFrame objects with NA values are ignored

• SpatialPolygonsDataFrame objects without neighbors are ignored

• SpatialPolygonsDataFrame input must have a valid Class and ID field. ID field must be contained of unique numbers

ggRaver/Lslide documentation built on April 8, 2022, 7:14 a.m.