Update (a subset of) an existing Zarr array
Arguments
- zarr_array_path
Character vector of length 1 giving the path to the Zarr array that is to be modified.
- x
The R array (or object that can be coerced to an array) that will be written to the Zarr array.
- index
A list with the same length as the number of dimensions of the target array. This argument indicates which elements in the target array should be updated.
Value
The function is primarily called for the side effect of writing to
disk. Returns (invisibly) TRUE if the array is successfully updated.
Examples
## first create a new, empty, Zarr array
new_zarry_array <- file.path(tempdir(), "new_array.zarr")
create_empty_zarr_array(
zarr_array_path = new_zarry_array, dim = c(20, 10),
chunk_dim = c(10, 5), data_type = "double"
)
## create a matrix smaller than our Zarr array
small_matrix <- matrix(runif(6), nrow = 3)
## insert the matrix into the first 3 rows, 2 columns of the Zarr array
update_zarr_array(new_zarry_array, x = small_matrix, index = list(1:3, 1:2))
## reading back a slightly larger subset,
## we can see only the top left corner has been changed
read_zarr_array(new_zarry_array, index = list(1:5, 1:5))
#> [,1] [,2] [,3] [,4] [,5]
#> [1,] 0.4841195 0.5454252 0 0 0
#> [2,] 0.5674063 0.7596780 0 0 0
#> [3,] 0.7539531 0.2129675 0 0 0
#> [4,] 0.0000000 0.0000000 0 0 0
#> [5,] 0.0000000 0.0000000 0 0 0