remove all Roadmap points pending a PDEP

Author: simonjayhawkins

web/pandas/about/roadmap.md

@@ -35,127 +35,3 @@ For more information about PDEPs, and how to submit one, please refer to
 
 {% endfor %}
 
-## Roadmap points pending a PDEP
-
-<div class="alert alert-warning" role="alert">
-  pandas is in the process of moving roadmap points to PDEPs (implemented in
-  August 2022). During the transition, some roadmap points will exist as PDEPs,
-  while others will exist as sections below.
-</div>
-
-### Apache Arrow interoperability
-
-[Apache Arrow](https://arrow.apache.org) is a cross-language development
-platform for in-memory data. The Arrow logical types are closely aligned
-with typical pandas use cases.
-
-We'd like to provide better-integrated support for Arrow memory and
-data types within pandas. This will let us take advantage of its I/O
-capabilities and provide for better interoperability with other
-languages and libraries using Arrow.
-
-### Decoupling of indexing and internals
-
-The code for getting and setting values in pandas' data structures
-needs refactoring. In particular, we must clearly separate code that
-converts keys (e.g., the argument to `DataFrame.loc`) to positions from
-code that uses these positions to get or set values. This is related to
-the proposed BlockManager rewrite. Currently, the BlockManager sometimes
-uses label-based, rather than position-based, indexing. We propose that
-it should only work with positional indexing, and the translation of
-keys to positions should be entirely done at a higher level.
-
-Indexing is a complicated API with many subtleties. This refactor will require care
-and attention. The following principles should inspire refactoring of indexing code and
-should result on cleaner, simpler, and more performant code.
-
-1. Label indexing must never involve looking in an axis twice for the same label(s).
-This implies that any validation step must either:
-
-  * limit validation to general features (e.g. dtype/structure of the key/index), or
-  * reuse the result for the actual indexing.
-
-2. Indexers must never rely on an explicit call to other indexers.
-For instance, it is OK to have some internal method of `.loc` call some
-internal method of `__getitem__` (or of their common base class),
-but never in the code flow of `.loc` should `the_obj[something]` appear.
-
-3. Execution of positional indexing must never involve labels (as currently, sadly, happens).
-That is, the code flow of a getter call (or a setter call in which the right hand side is non-indexed)
-to `.iloc` should never involve the axes of the object in any way.
-
-4. Indexing must never involve accessing/modifying values (i.e., act on `._data` or `.values`) more than once.
-The following steps must hence be clearly decoupled:
-
-  * find positions we need to access/modify on each axis
-  * (if we are accessing) derive the type of object we need to return (dimensionality)
-  * actually access/modify the values
-  * (if we are accessing) construct the return object
-
-5. As a corollary to the decoupling between 4.i and 4.iii, any code which deals on how data is stored
-(including any combination of handling multiple dtypes, and sparse storage, categoricals, third-party types)
-must be independent from code that deals with identifying affected rows/columns,
-and take place only once step 4.i is completed.
-
-  * In particular, such code should most probably not live in `pandas/core/indexing.py`
-  * ... and must not depend in any way on the type(s) of axes (e.g. no `MultiIndex` special cases)
-
-6. As a corollary to point 1.i, `Index` (sub)classes must provide separate methods for any desired validity check of label(s) which does not involve actual lookup,
-on the one side, and for any required conversion/adaptation/lookup of label(s), on the other.
-
-7. Use of trial and error should be limited, and anyway restricted to catch only exceptions
-which are actually expected (typically `KeyError`).
-
-  * In particular, code should never (intentionally) raise new exceptions in the `except` portion of a `try... exception`
-
-8. Any code portion which is not specific to setters and getters must be shared,
-and when small differences in behavior are expected (e.g. getting with `.loc` raises for
-missing labels, setting still doesn't), they can be managed with a specific parameter.
-
-### Numba-accelerated operations
-
-[Numba](https://numba.pydata.org) is a JIT compiler for Python code.
-We'd like to provide ways for users to apply their own Numba-jitted
-functions where pandas accepts user-defined functions (for example,
-`Series.apply`,
-`DataFrame.apply`,
-`DataFrame.applymap`, and in groupby and
-window contexts). This will improve the performance of
-user-defined-functions in these operations by staying within compiled
-code.
-
-### Documentation improvements
-
-We'd like to improve the content, structure, and presentation of the
-pandas documentation. Some specific goals include
-
--   Overhaul the HTML theme with a modern, responsive design
-    (`15556`)
--   Improve the "Getting Started" documentation, designing and writing
-    learning paths for users different backgrounds (e.g. brand new to
-    programming, familiar with other languages like R, already familiar
-    with Python).
--   Improve the overall organization of the documentation and specific
-    subsections of the documentation to make navigation and finding
-    content easier.
-
-### Performance monitoring
-
-Pandas uses [airspeed velocity](https://asv.readthedocs.io/en/stable/)
-to monitor for performance regressions. ASV itself is a fabulous tool,
-but requires some additional work to be integrated into an open source
-project's workflow.
-
-The [asv-runner](https://github.com/asv-runner) organization, currently
-made up of pandas maintainers, provides tools built on top of ASV. We
-have a physical machine for running a number of project's benchmarks,
-and tools managing the benchmark runs and reporting on results.
-
-We'd like to fund improvements and maintenance of these tools to
-
--   Be more stable. Currently, they're maintained on the nights and
-    weekends when a maintainer has free time.
--   Tune the system for benchmarks to improve stability, following
-    <https://pyperf.readthedocs.io/en/latest/system.html>
--   Build a GitHub bot to request ASV runs *before* a PR is merged.
-    Currently, the benchmarks are only run nightly.