create_bm: Create base map

In krietsch/auksRuak: Analyse and visualise spatial data from Red Phalaropes

Create base map

Description

Use open street map data to create a basemap with the extent of the data

Usage

create_bm(
  DT,
  lat = "lat",
  lon = "lon",
  buffer = 1000,
  sc_dist,
  squared = FALSE,
  projection = paste0("+proj=laea +lat_0=90 +lon_0=-156.653428 +x_0=0 +y_0=0",
    " +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 ")
)

Arguments

DT	Name of the data.table
lat	Name of the column with latitude (as.character)
lon	Name of the column with longitude (as.character)
buffer	Buffer around the data
sc_dist	Distance of the scale
squared	If true buffer is created around the centre and outline squared
projection	Projection of the data (default is equal area with centre Barrow)

Value

bm, a ggplot2 base map

Examples

# create table with two points
DT = data.table(name = c('NARL', 'Utqiagvik'),
                lat  = c(71.320854, 71.290246),
                lon  = c(-156.648210, -156.788622))

# change projection
st_transform_DT(DT)

# create base map
bm = create_bm(DT)
bm

krietsch/auksRuak documentation built on Feb. 15, 2023, 2:44 p.m.