Getting ready for release 4.6.0

Author: FrancescAlted

ANNOUNCE.rst

@@ -1,41 +1,49 @@
-Announcing Python-Blosc2 4.5.1
+Announcing Python-Blosc2 4.6.0
 ==============================
 
-We are happy to announce this release, which builds the ``b2view`` terminal
-data viewer into a richer **data-exploration** tool, upgrades the bundled
-**C-Blosc2 to 3.1.4**, and promotes **WASM/Pyodide to a fully supported
-platform**.
+We are happy to announce this release, which sharpens the **columnar / query
+side** of blosc2: zero-copy sorted views, queries over string (dictionary)
+columns, a more flexible and faster ``group_by``, and an ``b2view`` terminal
+browser that can now group, sort, and plot interactively.
 
 The main highlights are:
 
-- **Scatter plots in b2view**: from a column plot, press ``s`` to scatter the
-  current column against another column you pick from a list — column-vs-column
-  over the current (zoomed) row range — and ``h`` for a high-resolution
-  ``matplotlib`` scatter.  The high-res view of a 1-D series is now a min/max
-  envelope too, with a new ``r`` key to toggle the raw values.
-
-- **Searchable pickers**: the ``c`` go-to-column key now opens a searchable,
-  selectable column list (type to filter, arrows, Enter) for CTables, and ``/``
-  opens a searchable multi-select to choose which columns are shown.
-
-- **One-shot demo download**: ``b2view --download`` fetches a demo bundle
-  (``chicago-taxi-flat.b2z`` by default) into the current directory if it is not
-  already there, then opens it — a zero-setup way to try the viewer.
-
-- **Interaction fixes**: go-to-row/column pre-fills are now pre-selected (the
-  first keystroke replaces them), and ``escape`` keeps its documented layered
-  exit even while a panel is maximized (use ``r`` to restore).  Plus a refreshed
-  header, a filename label in the title, and ``CTable.info`` now showing
-  per-column compressed sizes.
-
-A quick taste — grab the demo and start exploring::
-
-    $ pip install blosc2 --upgrade
+- **Zero-copy sorted views**: ``CTable.sort_by(..., view=True)`` returns a
+  lightweight sorted view that shares the parent's column data and gathers rows
+  on demand — no whole-table copy.  Sorting on a fully indexed column streams
+  straight from the index, so reading a sorted slice of a huge (on-disk) table
+  is as easy as ``t.sort_by("col", view=True)[:10]``.
+
+- **Queries over string columns**: ``where`` expressions now work on
+  dictionary-encoded (string) columns, including membership tests such as
+  ``'"Acme" in company'``, filtering categorical text without decoding the whole
+  column.
+
+- **Smarter, faster group_by**: ``group_by(...).agg()`` accepts flexible
+  aggregation specs and explicit output names (pandas-style), a new tri-state
+  ``sort=`` (``None``/``True``/``False``) sorts only when cheap, the last
+  grouping is memoized, and ``min``/``max``/``argmin``/``argmax`` are
+  accelerated from per-block index summaries instead of decompressing data.
+
+- **b2view grows up**: interactive **group-by** (``G``, including float keys),
+  **sort-by-column** (``S``, zero-copy via the index), and much **better plots**
+  — bars for categorical keys, lines/stems for numeric keys, hi-res variants for
+  every plot type, and ``--max`` to maximize a panel.  ``b2view`` is now an
+  **opt-in extra** (``pip install "blosc2[tui]"``), so a plain
+  ``pip install blosc2`` stays lean.
+
+- **Fixes & maintenance**: the bundled **C-Blosc2 is upgraded to 3.1.5**, the
+  open-file cache now validates cached handles against the file's fingerprint (so
+  a file changed underneath an open handle is never served stale), plus
+  compatibility with **NumPy 2.5**.
+
+A quick taste — grab a table and explore it::
+
+    $ pip install "blosc2[tui]" --upgrade
     $ b2view --download --panel data
 
-Press ``p`` to plot a column, ``s`` to scatter it against another, and ``h``
-for a high-resolution view — all without decompressing anything you do not look
-at.
+Press ``G`` to group, ``S`` to sort, and ``p`` to plot a column — all without
+decompressing anything you do not look at.
 
 Install it with::
 

RELEASE_NOTES.md

@@ -1,8 +1,26 @@
 # Release notes
 
-## Changes from 4.5.1 to 4.5.2
+## Changes from 4.5.1 to 4.6.0
 
-XXX version-specific blurb XXX
+### `CTable.sort_by(view=True)`: zero-copy sorted views
+
+- `CTable.sort_by()` now accepts **`view=True`**, returning a lightweight
+  **sorted view** that shares the parent's column data and gathers rows on
+  demand in sorted order — no whole-table copy.  This is ideal for reading a
+  sorted slice of a large (possibly on-disk) table::
+
+      t.sort_by("col", view=True)[:10]      # top-10 without materialising
+
+  Sorting on a **fully indexed** column streams directly from the index, so the
+  table is never materialised.  Multi-column sorts and dotted (nested) leaf
+  names are supported (e.g. `t.sort_by(["trip.begin.lon", "payment.fare"],
+  ascending=[True, False])`).
+
+### `where` on dictionary (string) columns
+
+- `where` expressions now work over **dictionary-encoded (string) columns**,
+  including membership tests such as `'"Acme" in company'`, so categorical
+  text columns can be filtered without decoding the whole column.
 
 ### `b2view` is now an opt-in extra
 
@@ -64,6 +82,49 @@ XXX version-specific blurb XXX
     keys were already ascending; the generic Python fallback stays unsorted.
     Pass `sort=False` to opt out.
 
+### Accelerated reductions from index summaries
+
+- `min`/`max` on indexed `Column`s, and `argmin`/`argmax` inside `group_by`, are
+  now **accelerated using the index's per-block min/max summaries**: when an
+  index is available these reductions run from the precomputed summaries instead
+  of decompressing the underlying data, which is dramatically faster on large
+  columns.  A fast path also builds **min/max envelope plots** from any index.
+- The **last `group_by` operation is memoized** and reused when the same
+  grouping is requested again, avoiding recomputation in interactive / repeated
+  workflows (e.g. `b2view`).
+
+### b2view: group-by, sort, and richer plots
+
+- **Interactive group-by (`G`)**: group a `CTable` by a column (integer, string,
+  or now **float** keys) directly in the viewer, with a three-list / two-column
+  menu; while grouped, `S`/`R` operate on the grouped result and the data
+  panel's subtitle shows a `G(roup)` chip.  The last grouping is memoized for
+  instant reuse.
+- **Sort by column (`S`)**: sort a `CTable` by a **fully indexed** column via a
+  dropdown (`R` toggles reverse) as a zero-copy `sort_by(view=True)` that streams
+  from the index — the table is never materialised, `Esc` restores the original
+  order, and a `SORTED` chip shows in the status bar.  Non-indexed columns can
+  now be sorted too.  Sort and filter are mutually exclusive; a row window
+  composes over a sort, and an `f`ilter is preserved across `S`ort / `G`roup.
+- **Better plots of grouped/sorted views**: a grouped view plots **bars for a
+  categorical key** and **lines for a numeric key**; numeric-key group plots
+  render as **stem/impulse charts** rather than misleading connected lines.  Bar
+  plots gain an `h`i-res counterpart mirroring the line/scatter plots, and `+`/`-`
+  zoom about the view's left edge.
+- **`--max`** maximizes the current panel, and `escape` is now the single,
+  consistent way to back out of every modal.
+
+### Other / bug fixes
+
+- **C-Blosc2 upgraded to 3.1.5.**
+- **Open-file cache correctness**: cached open handles are now validated against
+  the file's fingerprint (`st_mtime_ns`, `st_size`) and cached index handles are
+  released when a table closes, so a file changed underneath an open handle is no
+  longer served stale.
+- **NumPy 2.5 compatibility**: adjusted for deprecations in NumPy 2.5.
+- Substantially **reduced test-suite runtime**, and emscripten builds no longer
+  attempt to spawn subprocesses (unsupported there).
+
 ## Changes from 4.5.0 to 4.5.1
 
 This follow-up release builds the `b2view` terminal viewer into a richer

pyproject.toml

@@ -41,7 +41,7 @@ dependencies = [
     "rich",
     "threadpoolctl; platform_machine != 'wasm32'",
 ]
-version = "4.5.2.dev0"
+version = "4.6.0"
 [project.entry-points."array_api"]
 blosc2 = "blosc2"
 

src/blosc2/version.py

@@ -1,2 +1,2 @@
-__version__ = "4.5.2.dev0"
+__version__ = "4.6.0"
 __array_api_version__ = "2024.12"