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Create a ggplot2 layer with map markers or numbered markers

Source: R/layer_markers.R
layer_markers.Rd

If get is TRUE, groupname_col, group_meta, crs, and fn is all passed on to make_markers.

Usage

layer_markers(
  data,
  mapping = NULL,
  geom = "sf",
  make = FALSE,
  groupname_col = NULL,
  group_meta = NULL,
  crs = NULL,
  number = FALSE,
  num_by_group = FALSE,
  num_style = NULL,
  num_start = 1,
  suffix = NULL,
  sort = "dist_xmin_ymax",
  desc = FALSE,
  fn = NULL,
  ...
)

layer_numbers(
  data,
  mapping = NULL,
  geom = "label",
  make = FALSE,
  groupname_col = NULL,
  style = "roundrect",
  size = 5,
  sort = "dist_xmin_ymax",
  num_by_group = FALSE,
  num_style = NULL,
  num_start = 1,
  suffix = NULL,
  desc = FALSE,
  fn = NULL,
  crs = NULL,
  label.size = 0,
  label.padding = ggplot2::unit(size/10, "lines"),
  label.r = label.padding * 1.5,
  hjust = 0.5,
  vjust = 0.5,
  ...
)

Arguments

data

Data with markers, passed to data parameter of get_location_data()

mapping

Set of aesthetic mappings created by aes() or aes_(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.

geom

The geometric object to use display the data

make

If TRUE, pass data to make_markers.

groupname_col

Group column name, used to join group metadata if group_meta is a non-spatial data frame; Default: NULL

group_meta

Group metadata as a data frame or sf object that intersect with markers; Default: NULL

crs

Coordinate reference system for markers, Default: NULL

number

If TRUE, number markers using layer_markers() (not currently supported)

num_by_group

If TRUE, numbers are added by group based on groupname_col.

num_style

Style of enumeration, either "arabic", "alph", "Alph", "roman", "Roman"

num_start

Starting number; defaults to 1.

suffix

Character to appended to "number" column. (e.g. "." for "1." or ":" for "1:"). Can also be a character vector with the same length as the number column.

sort

Sort column name, Default: "dist_xmin_ymax".

desc

If TRUE, sort descending; default FALSE.

fn

Function to apply to data before results; gives warning if data is grouped; Default: NULL

...

Additional parameters passed to layer_location_data()

style

Style of number markers to map; defaults to "roundrect".

size

Marker size, Default: 5

label.size

Size of label border, in mm.

label.padding

Amount of padding around label. Defaults to 0.25 lines.

label.r

Radius of rounded corners. Defaults to 0.15 lines.

hjust, vjust

Horizontal and vertical justification.

Value

ggplot2 layers

See also

Other layer: layer_frame(), layer_icon(), layer_location_data(), layer_mask(), layer_neatline(), layer_scaled()

Examples

nc <- read_sf_path(system.file("shape/nc.shp", package = "sf"))
nc <- st_transform_ext(nc, 3857)

basemap <-
  ggplot2::ggplot() +
  layer_location_data(
    data = nc,
    fill = NA
  ) +
  ggplot2::theme_void()

basemap +
  layer_markers(
    data = nc[1:10],
    mapping = ggplot2::aes(size = AREA),
    make = TRUE
  )


large_nc <-
  get_location_data(
    data = nc,
    fn = ~ dplyr::filter(.x, AREA > 0.2)
  )

basemap +
  layer_numbers(
    data = large_nc,
    mapping = ggplot2::aes(fill = NAME),
    sort = "dist_xmid_ymid",
    num_style = "Roman",
    geom = "label",
    size = 3
    ) +
  ggplot2::guides(fill = "none")