rg_biv_cmat: Bivariate plotting of raster maps
In sitscholl/Rgadgets: Contains various utility functions developed during the PhD

Description Usage Arguments Functions Source Examples

These functions can be used to combine two raster layers in a bivariate plot. To generate a bivariate plot, first a matrix with the color codes and a raster layer that is a combination of the two layers that should be plotted have to be calculated. The function rg_big_cmat can be used to generate the color matrix and the function rg_biv_create_raster to combine the two single raster files. The outputs of these two functions are then used in the function rg_biv_plot_raster to create the final plot. The function rg_biv_get_legend can optionally be used to inspect the final legend and is used internally by the function rg_biv_plot_raster to create the legend for the plot.

rg_biv_cmat(
  breaks,
  style = 1,
  upper.left = NULL,
  upper.right = NULL,
  lower.left = NULL,
  lower.right = NULL
)

rg_biv_get_legend(
  cmat,
  xlab = "",
  ylab = "",
  label.size = 12,
  label.color = "black"
)

rg_biv_create_raster(x, y, breaks)

rg_biv_plot_raster(
  bivraster,
  cmat,
  xlab = "",
  ylab = "",
  border = NULL,
  crs = "+init=epsg:4326",
  na.value = "transparent",
  legend.height = 0.25,
  legend.width = 0.25,
  legend.x = 0.75,
  legend.y = 0.2,
  limits = NULL
)

`breaks`	integer, number of breaks used to generate the bivariate color scale
`style`	integer, number between 1 and 9 to select different predefined color combinations
`upper.left`	string, upper left color
`upper.right`	string, upper right color
`lower.left`	string, lower left color
`lower.right`	string, lower right color
`cmat`	matrix, a matrix with hexcolor codes such as returned from the function `rg_biv_cmat`
`xlab`	string, x-label of the legend
`ylab`	string, y-label of the legend
`label.size`	numeric, size of legend labels
`label.color`	string, color of legend label
`x`	raster layer, first layer for bivariate plot
`y`	raster layer, second layer for bivariate plot
`bivraster`	raster, the raster object returned from the function `rg_biv_create_raster`
`border`	sf object, optionally plot an sf object as border around raster. Make sure the sf object has the same crs as the bivraster
`crs`	string, specification of the coordinate system you want to plot the bivraster in. Per Default uses EPSG:4326
`na.value`	string, color for NA values
`legend.height`	numeric, height of legend
`legend.width`	numeric, width of legend
`legend.x`	numeric, relative x position of legend
`limits`	optionally zoom in into plot using x and y limits. Use the syntax limits = c(xmin, xmax, ymin, ymax).
`legnend.y`	numeric, relative y position of legend

rg_biv_cmat: Generate color matrix
rg_biv_get_legend: Generate legend from color matrix
rg_biv_create_raster: Combine both single raster files to bivariate raster
rg_biv_plot_raster: Create bivariate plot

#https://stackoverflow.com/questions/54144269/bivariate-choropleth-map-in-r

breaks <- 3
cmat <- rg_biv_cmat(breaks, style = 1)
legend <- rg_biv_get_legend(cmat, xlab = 'Gain', ylab = 'Loss')
xy <- rg_biv_create_raster(x, y, breaks)
map <- rg_biv_plot_raster(xy, cmat, border = st_border_proj, xlab = 'Gain', ylab = 'Loss', limits = c(10.7, 12, 46.2, 46.8))
map