Extract values from a raster to produce a scatterplot

Source: R/plot_scatter_f.R

Called by the plot_scatter module in the example app and samples values from a raster along with either the x or y coordinates of the points sampled

plot_scatter(raster, sample, axis, logger = NULL)

Arguments

raster

SpatRaster. Raster to be sampled

sample

numeric. Number of points to sample

axis

character. Which axis coordinates of the raster to return

logger

Stores all notification messages to be displayed in the Log Window. Insert the logger reactive list here for running in shiny, otherwise leave the default NULL

Value

a dataframe containing the axis values and the cell values

Author

Simon Smart simon.smart@cantab.net

Examples

if (check_suggests(example = TRUE)) {
  raster <- terra::rast(ncol = 8, nrow = 8)
  raster[] <- sapply(1:terra::ncell(raster), function(x){
     rnorm(1, ifelse(x %% 8 != 0, x %% 8, 8), 3)})
  scatterplot <- plot_scatter(raster, sample = 10, axis = "y")
} else {
  message('reinstall with install.packages("shinyscholar", dependencies = TRUE)
  to run this example')
}