fcircles: Fresnel Circles

In lbuk/fmap: Fresnel Maps with Equal-Area Concentric Circular Zones (or Annuli)

Fresnel Circles

Description

Function for creating Fresnel circles polygons for mapping. Fresnel circles consist of a central circle as well as concentric annuli, all of which are equal in area.

Usage

fcircles(
  ncircles,
  radius_inner = NULL,
  radius_outer = NULL,
  lat = NULL,
  lon = NULL,
  geo_centre = NULL
)

Arguments

ncircles	Number of concentric circular zones of equal area (i.e. Fresnel circles) including the inner circle and annuli
radius_inner	Radius of innermost Fresnel circle in metres
radius_outer	Radius of outermost Fresnel circle in metres
lat	Latitude of the centre of the Fresnel circles
lon	Longitude of the centre of the Fresnel circles
geo_centre	A spatial dataset containing the coordinates of the centre of the Fresnel circles

Value

An sf dataset of Fresnel circle polygons with a custom Azimuthal Equidistant (AEQD) CRS.

Examples

library(sf)
library(dplyr)

# Load the sf dataset of Soho pumps
data(soho_pumps)

# Filter the Broad Street Pump from the Soho pumps dataset
bstreet_pump <- soho_pumps %>% filter(soho.pump == "Broad Street")

# Polygonal data from the Fresnel circles
fcircles(radius_inner = 125, ncircles = 8, geo_centre = bstreet_pump)

lbuk/fmap documentation built on Nov. 23, 2024, 12:47 p.m.