STlist_to_disk: Move an STlist's count matrices to on-disk parquet

Source: R/store_parquet.R

Converts an in-memory STlist into one backed by parquet files, so data larger than memory can be held and read in slices.

STlist_to_disk(x = NULL, root = NULL, overwrite = FALSE)

Arguments

x

an STlist

root

directory to write the store into. Created if absent

overwrite

logical, whether to overwrite an existing store at root

Value

an STlist whose count slots are on-disk backed

Details

Opt-in and reversible. @counts and @tr_counts elements are replaced by manifests describing per-sample parquet files; every other slot is untouched. All package functions continue to work, because slot reads go through internal accessors that materialize on demand – so this trades memory for I/O rather than changing results.

Matrices are stored in COO (long) form, one file per sample per slot, sorted by gene then cell. STlist_to_memory() reverses the conversion.

Note the store is a directory of files, not part of the R object. An STlist saved with saveRDS() records paths, so moving or deleting root breaks it; validate_store() reports that rather than failing obscurely later.