Gather views describe non-contiguous column (or row) subsets without
allocating a slice-sized matrix. shard-aware kernels can then choose to
pack the requested indices into scratch explicitly (bounded and reportable)
or run gather-aware compute paths.
Usage
view_gather(x, rows = NULL, cols)
Arguments
- x
A shared (share()d) atomic matrix (double/integer/logical/raw).
- rows
Row selector. NULL (all rows) or idx_range().
- cols
Integer vector of column indices (1-based).
Value
A shard_view_gather object describing the indexed column view.
Details
v1 note: only column-gather views are implemented (rows may be NULL or
idx_range()).
Examples
# \donttest{
m <- share(matrix(1:20, nrow = 4))
v <- view_gather(m, cols = c(1L, 3L))
# }