How to modify legend symbology and its placement in an aggplot?

[juandemedel]

Hello dear community @thomased, @Bisaloo. I've been working on an aggplot legend. This legend shows several lines. However, those lines are as thin as they can not be perceived easily in a plot. Besides, I would like to change the legend size and placement in the plot. Would you please give me some advice to fix it?

[Bisaloo]

Hi @juandemedel, thanks for opening this issue! I addressed the part about thin lines in legend in https://github.com/rmaia/pavo/commit/3e5c490e68d032edb49b1ffd4fd435de6f64feed. The lines in the legend will now have the same width as the lines in the plot, as determined by the lwd argument.

Before

#> Welcome to pavo 2! Take a look at the latest features (and update your bibliography) in our recent publication: Maia R., Gruson H., Endler J. A., White T. E. (2019) pavo 2: new tools for the spectral and spatial analysis of colour in R. Methods in Ecology and Evolution, 10, 1097-1107.

# Load reflectance data
data(sicalis)

# Create grouping variable based on spec names
bysic <- gsub("^ind[0-9].", "", names(sicalis)[-1])

aggplot(sicalis, bysic, legend = TRUE)

aggplot(sicalis, bysic, legend = TRUE, lwd = 3)

^{Created on 2022-06-19 by the reprex package (v2.0.1.9000)}

After (with pavo development version)

library(pavo)
#> Welcome to pavo 2! Take a look at the latest features (and update your bibliography) in our recent publication: Maia R., Gruson H., Endler J. A., White T. E. (2019) pavo 2: new tools for the spectral and spatial analysis of colour in R. Methods in Ecology and Evolution, 10, 1097-1107.

# Load reflectance data
data(sicalis)

# Create grouping variable based on spec names
bysic <- gsub("^ind[0-9].", "", names(sicalis)[-1])

aggplot(sicalis, bysic, legend = TRUE)

aggplot(sicalis, bysic, legend = TRUE, lwd = 3)

^{Created on 2022-06-19 by the reprex package (v2.0.1.9000)}

[Bisaloo]

For the second part, about custom placement, I cannot think about a great solution for now. You best bet at the moment is probably to create the legend yourself manually. Here is an example of how you might do it:

library(pavo)
#> Welcome to pavo 2! Take a look at the latest features (and update your bibliography) in our recent publication: Maia R., Gruson H., Endler J. A., White T. E. (2019) pavo 2: new tools for the spectral and spatial analysis of colour in R. Methods in Ecology and Evolution, 10, 1097-1107.

# Load reflectance data
data(sicalis)

# Create grouping variable based on spec names
bysic <- gsub("^ind[0-9].", "", names(sicalis)[-1])

# Set custom parameters
my_cols <- c(
  "#E41A1C", "#377EB8", "#4DAF4A"
)
my_lwd <- 3

aggplot(sicalis, bysic, lcol = my_cols, lwd = my_lwd)

# Create custom legend:
# The first argument can be a keyword like "bottomright", "bottom", 
# "bottomleft", "left", "topleft", "top", "topright", "right" and "center", or
# x, y coordinates. See ?legend for more information
legend("bottomright", bty = "n", legend = unique(bysic), col = my_cols, lty = 1, lwd = my_lwd)

^{Created on 2022-06-19 by the reprex package (v2.0.1.9000)}

Please let us know if this helps!

[juandemedel]

Thank you so much.