map_multiples: Visualize multiple distributions in a series of maps
In colorist: Coloring Wildlife Distributions in Space-Time

Description Usage Arguments Details Value See Also Examples

This function enables visualization of distributional information in a series of small multiples by combining distribution metrics and an HCL color palette.

map_multiples(
  x,
  palette,
  ncol,
  lambda_i = 0,
  labels = NULL,
  return_type = c("plot", "df")
)

`x`	RasterStack of distributions processed by `metrics_pull()`.
`palette`	data frame containing an HCL color palette generated using `palette_timecycle()`, `palette_timeline()`, or `palette_set()`.
`ncol`	integer specifying the number of columns in the grid of plots.
`lambda_i`	number that allows visual tuning of intensity values via the `scales::modulus_trans()` function (see Details). Negative numbers increase the opacity of cells with low intensity values. Positive numbers decrease the opacity of cells with low intensity values.
`labels`	character vector of layer labels for each plot. The default is to not show labels.
`return_type`	character specifying whether the function should return a `ggplot2` plot object ("plot") or data frame ("df"). The default is to return a `ggplot2` object.

The lambda_i parameter allows for visual tuning of intensity values with unusual distributions. For example, distributions often contain highly skewed intensity values because individuals spend a vast majority of their time within a relatively small area or because populations are relatively dense during some seasons and relatively dispersed during others. This can make visualizing distributions a challenge. The lambda_i parameter transforms intensity values via the scales::modulus_trans() function, allowing users to adjust the relative visual weight of high and low intensity values.

By default, or when return_type = "plot", the function returns a map that is a ggplot2 plot object.

When return_type = "df", the function returns a data frame containing eight columns:

x,y: coordinates of raster cell centers.
cell_number: integer indicating the cell number.
layer_cell: a unique ID for the cell within the layer in the format "layer-cell_number".
intensity: maximum cell value across layers divided by the maximum value across all layers and cells; mapped to alpha level.
specificity: the degree to which intensity values are unevenly distributed across layers; mapped to chroma.
layer_id: the identity of the raster layer from which an intensity value was pulled; mapped to hue.
color: the hexadecimal color associated with the given layer and specificity values.

Other map: map_single()

# load fisher data
data("fisher_ud")

# prepare data
r <- metrics_pull(fisher_ud)

# generate palette
pal <- palette_timeline(fisher_ud)

# produce maps, adjusting lambda_i to make areas that were used less
# intensively more conspicuous
map_multiples(r, pal, lambda_i = -5, labels = paste("night", 1:9))