NEWS

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delarr 0.1.0

Broadcasting

• Broadcasting a bare length-n vector against a square n-by-n matrix is ambiguous (the length matches both dimensions). delarr continues to resolve this to row-aligned (one value per row, matching base R recycling), but now emits a warning at operation-construction time so the choice is explicit. Pass a conformable matrix (e.g. matrix(v, n, n, byrow = TRUE)) for column alignment. Silence the warning with options(delarr.warn_ambiguous_broadcast = FALSE).

First public release.

Features

• Lazy delarr arrays with a fused, chunk-aware execution engine.
• Pipelined verbs: d_map(), d_map2(), d_center(), d_scale(), d_zscore(), d_detrend(), d_reduce(), d_where(), and d_aperm(), all of which stay lazy until collect().
• Lazy, block-aware matrix products via d_matmul().
• Storage backends: delarr_mem() (in-memory matrices and N-d arrays), delarr_hdf5() (HDF5 datasets, including N-d), delarr_mmap() (memory-mapped 2D matrices), and delarr_backend() for custom pull functions.
• Streaming output to disk with hdf5_writer() and collect(into = ...).
• block_apply() for chunk-wise computation.
• Getting-started and advanced vignettes plus benchmark scripts in notes/.

Dependencies

• The core package depends only on rlang. The hdf5r and mmap backends are now optional (Suggests); the corresponding constructors raise an informative error when the package is not installed.