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Add a PhyloPic legend for a base R plot

Source: R/add_phylopic_legend.R
add_phylopic_legend.Rd

Specify existing images, taxonomic names, or PhyloPic uuids to add PhyloPic silhouettes as a legend to an existing base R plot (like legend()).

Usage

add_phylopic_legend(
  x,
  y = NULL,
  legend,
  img = NULL,
  name = NULL,
  uuid = NULL,
  ysize = deprecated(),
  height = NULL,
  color = NA,
  fill = "black",
  ...
)

Arguments

x

numeric or character. Either the x coordinate to be used to position the legend or a keyword accepted by legend() such as "topleft", "topright", "bottomleft", and "bottomright".

y

numeric. The y coordinate to be used to position the legend. Can be NULL (default) if using keywords in x.

legend

character. A character vector of the labels to appear in the legend.

img

A Picture or png array object, e.g., from using get_phylopic().

name

character. A taxonomic name to be passed to get_uuid().

uuid

character. A valid uuid for a PhyloPic silhouette (such as that returned by get_uuid() or pick_phylopic()).

ysize

[Deprecated] use the height argument instead.

height

numeric. Height of the legend silhouette(s). The width is determined by the aspect ratio of the original image.

color

character. Color of silhouette outline. If "original" or NA is specified, the original color of the silhouette outline will be used (usually the same as "transparent"). To remove the outline, you can set this to "transparent".

fill

character. Color of silhouette. If "original" is specified, the original color of the silhouette will be used (usually the same as "black"). If color is specified and fill is NA, color will be used as the fill color (for backwards compatibility). To remove the fill, you can set this to "transparent".

...

Additional arguments passed to legend().

Details

This function can be used to add PhyloPic silhouettes as a legend to a base R plot. Arguments available in legend() can be used and passed via .... Note that not all arguments in legend() are compatible with add_phylopic_legend(). These include arguments for modifying lines (e.g. lty, lwd, seg.len), points (e.g. pch, pt.lwd), and shading (e.g. angle and density). This is due to add_phylopic_legend() using add_phylopic_base() to generate the legend symbols. However, arguments for adjusting the legend appearance such as text (e.g. cex), legend box (e.g. bg), and color (e.g. border) are compatible.

Examples

# Get UUIDs
uuids <- get_uuid(name = "Canis lupus", n = 2)
# Generate empty plot
plot(0:10, 0:10, type = "n", main = "Wolves")
# Add data points
add_phylopic_base(uuid = uuids,
  color = "black", fill = c("blue", "green"),
  x = c(2.5, 7.5), y = c(2.5, 7.5), height = 2)
# Add legend
add_phylopic_legend(uuid = uuids, 
  height = 0.5, color = "black", fill = c("blue", "green"), 
  x = "bottomright", legend = c("Wolf 1", "Wolf 2"),
  bg = "lightgrey")