Number of Points in Each Polygon

Description

Given a set of points, and a set of polygons, computes the number of points in each polygon.

Usage

poly.counts(pts, polys)

Arguments

Value

A list of integers of the same length as the number of polygons in polys, giving the number of points from pts.

Author(s)

Chris Brunsdon

Examples

# Data for New Haven to use in example
data(newhaven)
# How many breaches of peace in each census block?
n.breach = poly.counts(breach,blocks)
# Compute densities and map them
choropleth(blocks,n.breach/poly.areas(blocks))

Results

R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(GISTools)
Loading required package: maptools
Loading required package: sp
Checking rgeos availability: TRUE
Loading required package: RColorBrewer
Loading required package: MASS
Loading required package: rgeos
rgeos version: 0.3-19, (SVN revision 524)
 GEOS runtime version: 3.5.0-CAPI-1.9.0 r4084 
 Linking to sp version: 1.2-3 
 Polygon checking: TRUE 

> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/GISTools/poly.counts.Rd_%03d_medium.png", width=480, height=480)
> ### Name: Point in Polygon Counts
> ### Title: Number of Points in Each Polygon
> ### Aliases: poly.counts
> 
> ### ** Examples
> 
> # Data for New Haven to use in example
> data(newhaven)
> # How many breaches of peace in each census block?
> n.breach = poly.counts(breach,blocks)
> # Compute densities and map them
> choropleth(blocks,n.breach/poly.areas(blocks))
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>