[ENH] Improve conditional_join (#1224)

* úpdates´

* updates

* update comments

* spelling fix

* minor clean

* better logic for non equi join check

* better logic for non equi join check

* better logic for non equi join check

* restore strictness on column dtypes and simplify logic for non equi join check

* fix logic

* allow selection of either only df or right

* add indicator parameter

* add tests for indicator parameter

* add version added to docs

* changelog

* improve perf for empty dataframe

* simplify logic

* performance improvement for range joins if use_numba=False - occurs for scenarios where the range columns are both monotonically increasing when sorted

* add comments

* refactor numba

* update to indicator arg when creating the final dataframe

* improve logic for dataframe creation with `indicator`

* further updates to dataframe creation

* cleanup

* fix conditional_join.ipynb

* add test for multiindex with indicator parameter

* use np.delete instead of np.bincount

* remove dead code

* fix type hint

* rebase

* rebase

* rebase

* rebase

* rebase

* cleanup

* fix conditional_join.ipynb

* edit docs to match updated google style

---------

Co-authored-by: ¨samukweku¨ <root@localhost>
Co-authored-by: samuel.oranyeli <samuel.oranyeli@grow.inc>
Co-authored-by: Eric Ma <ericmjl@users.noreply.github.com>

CHANGELOG.md

@@ -11,6 +11,7 @@
 -   [INF] Prevent selection of chevrons (`>>>`) and outputs in Example code blocks. PR #1237 @thatlittleboy
 -   [DEPR] Add deprecation warnings for `process_text`, `rename_column`, `rename_columns`, `filter_on`, `remove_columns`, `fill_direction`. #1045 @samukweku
 -   [ENH] `pivot_longer` now supports named groups where `names_pattern` is a regular expression. A dictionary can now be passed to `names_pattern`, and is internally evaluated as a list/tuple of regular expressions. Issue #1209 @samukweku
+-   [ENH] Improve selection in `conditional_join`. Issue #1223 @samukweku
 
 ## [v0.24.0] - 2022-11-12
 

examples/notebooks/conditional_join.ipynb

@@ -1447,9 +1447,9 @@
    "hash": "d4d1e4263499bec80672ea0156c357c1ee493ec2b1c70f0acce89fc37c4a6abe"
   },
   "kernelspec": {
-   "display_name": "Python 3.9.10 ('base')",
+   "display_name": "PyJanitor development",
    "language": "python",
-   "name": "python3"
+   "name": "pyjanitor-dev"
   },
   "language_info": {
    "codemirror_mode": {
@@ -1461,7 +1461,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.9.10"
+   "version": "3.9.15"
   },
   "orig_nbformat": 4
  },