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Open a Zarr-backed Daf store.

Source: R/zarr_format.R
zarr_daf.Rd

Path-aware constructor that picks the right backing store. A path ending in .daf.zarr (or any directory path) creates a DirStore. :memory: or NULL creates a DictStore. A path ending in .daf.zarr.zip creates an MmapZipStore (mmap-backed zip).

Usage

zarr_daf(
  uri = NULL,
  mode = c("r", "r+", "w", "w+"),
  name = NULL,
  packed = FALSE
)

Arguments

uri

Filesystem directory path, :memory:, or NULL.

mode

"r", "r+", "w", or "w+". "w" initializes a fresh empty store (creating the directory if needed). "w+" truncates any existing store and creates a fresh one. "r+" opens for read-write without truncating. "r" opens read-only.

name

Optional name; default derived from uri.

packed

If TRUE (write modes only), dense vectors, dense matrices, and sparse-component arrays that exceed the packed-write size threshold are written as sharded (compressed) Zarr v3 arrays instead of flat; scalars and axes always stay flat. Per-component and threshold-gated, so a store may mix flat and packed components. Tunable via options(dafr.packed_compression=, dafr.packed_compression_level=, dafr.packed_target_chunk_kb=).

Value

A ZarrDaf (writeable) or ZarrDafReadOnly.

Examples

tmp <- tempfile(fileext = ".daf.zarr")
d <- zarr_daf(tmp, mode = "w")
add_axis(d, "cell", c("c1", "c2"))