#!/usr/bin/env Rscript
##
## cf writing_dense_sparse.cc
##
## When run, this script will create a simple 2D dense array, write some sparse
## cells to it in a way that some space is empty, and read the entire array data
## back.
library(tiledb)
## Name of the array to create.
array_name <- "writing_dense_sparse_array"
## Path is either current directory, or a local config value is found
uri <- file.path(getOption("TileDB_Data_Path", "."), array_name)
create_array <- function(uri) {
## The array will be 4x4 with dimensions "rows" and "cols", with domain [1,4]
## and space tiles 2x2
dom <- tiledb_domain(dims = c(tiledb_dim("rows", c(1L,4L), 2L, "INT32"),
tiledb_dim("cols", c(1L,4L), 2L, "INT32")))
## Dense scheme, adding a single attribute "a" so each (i,j) cell can store an integer.
schema <- tiledb_array_schema(dom, attrs = c(tiledb_attr("a", type = "INT32")))
## Create the (empty) array on disk.
tiledb_array_create(uri, schema)
invisible(NULL)
}
write_array <- function(uri) {
data <- c(1L, 2L, 3L, 4L)
coords_rows <- c(1L, 2L, 4L, 1L)
coords_cols <- c(2L, 1L, 3L, 4L)
arr <- tiledb_array(uri, query_type="WRITE", is.sparse=FALSE)
arr[] <- data.frame(rows=coords_rows, cols=coords_cols, a=data)
invisible(NULL)
}
read_array <- function(uri) {
## opening in data.frame mode
## returning three vectors
arr <- tiledb_array(uri, return_as="data.frame")
dat <- arr[]
print(dat)
}
if (dir.exists(uri)) unlink(uri, recursive=TRUE)
create_array(uri)
write_array(uri)
read_array(uri)
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