create_colored_bm: Create colored base map

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

Create colored base map

Description

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

Usage

create_colored_bm(
  DT,
  lat = "lat",
  lon = "lon",
  buffer = 1000,
  aspect = "16:9",
  sc_dist,
  sc_location = "br",
  sc_cex = 0.7,
  sc_height = unit(0.25, "cm"),
  sc_pad_x = unit(0.25, "cm"),
  sc_pad_y = unit(0.5, "cm"),
  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
aspect	Set aspect ratio of the base map
sc_dist	Distance of the scale
sc_location	Where to put the scale bar ("tl" for top left, etc.)
sc_cex	Label size as numeric character expansion factor
sc_height	Thickness of the scale bar
sc_pad_x	Distance from edge of the scale bar (annotation_scale
sc_pad_y	Distance from edge of the scale bar (annotation_scale
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_colored_bm(DT)
bm

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