Overlays and extracts values at points from a list of raster layers defined as file names (e.g. GeoTiffs). Extends the extract function from the raster package. Especially suitable for extracting values of a large list of rasters that have not been organized into a mosaick (a virtual stack), for example a list of Landsat scenes.
# S4 method for SpatialPoints,character
extract(x, y,
path=".", ID = "SOURCEID",
method = "simple", is.pattern = FALSE, force.projection = TRUE,
NAflag = "", show.progress=TRUE, isFactor=FALSE, …)
# S4 method for SpatialPointsDataFrame,character
extract(x, y,
path = ".", ID = "SOURCEID",
method = "simple", is.pattern = FALSE, force.projection = TRUE,
NAflag = "", show.progress=TRUE, isFactor=FALSE, …)object of class "SpatialPoints*"
character; list of files that can be read using the raster function
optional working directory where the files are stored
character; column name for the unique identifier (if object is of class "SpatialPoints" "SOURCEID" column is automatically generated)
character; resampling method (see raster::extract)
logical; specifies whether the list is a pattern
logical; specifies whether the reprojection should be ignored
character; missing value flag (all missing values are removed by default)
logical; specifies whether to display the progress bar
logical; turns aggregation on off for factor type variable
additional arguments that can be passed to the raster::extract function
raster::extract, warp