I've created a list with raster filenames from a folder, then want to import those rasters into R in a "stack" using {terra}, and eventually am wanting to use {terra} to extract values from those rasters at points in a shapefile. My raster files are all uniquely named in my file folder; however, in some cases I have rasters that are named similarly (e.g., canflax2017.tif, canflax2018.tif, canflax2019.tif, canflax2018_137.tif, canflax2018_51.tif, canflax2017_137.tif, etc). When I get all the rasters in a "stack" it seems to cut off the year in the resulting raster name, but only for the filenames without a "_" in the raster name. For example, canflax2017, canflax2018, canflax2019 all have the name canflax and aren't unique, but canflax2018_137, canflax2018_51, and canflax2019_137 are fine and show the whole filename. Of course, then when I want to extract values from the stack, the columns for canflax2017, canflax2018, canflax2019 are just named canflax, canflax.1, canflax.2 etc. in the output dataframe. Any thoughts to ensure that the whole filename somehow gets incoporated into the stack information?
Code below:
library(terra)
rastsfilelist<-list.files(path="XXX/AllRasters",pattern="tif$",full.names = TRUE)
owl_stack<-rast(rastsfilelist)
owllocs <- vect('XX/shapefiletest.shp')
test<-extract(owl_stack,owllocs)
Here's the information regarding names for each raster in the stack enter image description here
Just make sure, the layer names in different rasters (files) have different names. An example below: layer names are the same regardless of file names until I change them.
l <- list.files(path = "/home/sapi/projekty/test", pattern = "above", full.names = TRUE)
l
#> [1] "/home/sapi/projekty/test/above_a.tif"
#> [2] "/home/sapi/projekty/test/above_b.tif"
#> [3] "/home/sapi/projekty/test/above_c.tif"
r <- terra::rast(l)
r
#> class : SpatRaster
#> dimensions : 25, 22, 3 (nrow, ncol, nlyr)
#> resolution : 8.181818, 7.2 (x, y)
#> extent : 0, 180, -90, 90 (xmin, xmax, ymin, ymax)
#> coord. ref. : lon/lat WGS 84 (EPSG:4326)
#> sources : above_a.tif
#> above_b.tif
#> above_c.tif
#> names : lyr.1, lyr.1, lyr.1
#> min values : 10, 10, 10
#> max values : 10, 10, 10
w <- terra::rast("/home/sapi/projekty/test/above_a.tif")
names(w) <- "other_name"
w
#> class : SpatRaster
#> dimensions : 25, 22, 1 (nrow, ncol, nlyr)
#> resolution : 8.181818, 7.2 (x, y)
#> extent : 0, 180, -90, 90 (xmin, xmax, ymin, ymax)
#> coord. ref. : lon/lat WGS 84 (EPSG:4326)
#> source : above_a.tif
#> name : other_name
#> min value : 10
#> max value : 10
terra::writeRaster(w, filename = "/home/sapi/projekty/test/above_d.tif", overwrite = TRUE)
l <- list.files(path = "/home/sapi/projekty/test", pattern = "above", full.names = TRUE)
x <- terra::rast(l)
x
#> class : SpatRaster
#> dimensions : 25, 22, 4 (nrow, ncol, nlyr)
#> resolution : 8.181818, 7.2 (x, y)
#> extent : 0, 180, -90, 90 (xmin, xmax, ymin, ymax)
#> coord. ref. : lon/lat WGS 84 (EPSG:4326)
#> sources : above_a.tif
#> above_b.tif
#> above_c.tif
#> above_d.tif
#> names : lyr.1, lyr.1, lyr.1, other_name
#> min values : 10, 10, 10, 10
#> max values : 10, 10, 10, 10
To change names you can use setNames() function like:
l[[1]] |>
terra::rast() |>
setNames(basename(l[[1]]))
#> class : SpatRaster
#> dimensions : 25, 22, 1 (nrow, ncol, nlyr)
#> resolution : 8.181818, 7.2 (x, y)
#> extent : 0, 180, -90, 90 (xmin, xmax, ymin, ymax)
#> coord. ref. : lon/lat WGS 84 (EPSG:4326)
#> source : above_a.tif
#> name : above_a.tif
#> min value : 10
#> max value : 10
Created on 2024-01-22 with reprex v2.1.0