add release date - update docs

Author: ilanschnell

CHANGE_LOG

@@ -1,4 +1,4 @@
-2025-08-XX   3.6.1:
+2025-08-12   3.6.1:
 -------------------
   * add development files for statistical tests in `devel/random/`
   * optimize `util.sum_indices()`

doc/changelog.rst

@@ -1,6 +1,14 @@
 Change log
 ==========
 
+**3.6.1** (2025-08-12):
+
+* add development files for statistical tests in ``devel/random/``
+* optimize ``util.sum_indices()``
+* fix RecursionError in ``util.random_k()``, see `#239 <https://github.com/ilanschnell/bitarray/issues/239>`__
+* add ``devel/test_sum_indices.py``
+
+
 **3.6.0** (2025-07-29):
 
 * add ``util.random_k()``, see `#237 <https://github.com/ilanschnell/bitarray/issues/237>`__

doc/reference.rst

@@ -1,7 +1,7 @@
 Reference
 =========
 
-bitarray version: 3.6.0 -- `change log <https://github.com/ilanschnell/bitarray/blob/master/doc/changelog.rst>`__
+bitarray version: 3.6.1 -- `change log <https://github.com/ilanschnell/bitarray/blob/master/doc/changelog.rst>`__
 
 In the following, ``item`` and ``value`` are usually a single bit -
 an integer 0 or 1.
@@ -577,7 +577,7 @@ This sub-module was added in version 1.2.
 
 ``sum_indices(a, /)`` -> int
    Return sum of indices of all active bits in bitarray ``a``.
-   This is equivalent to ``sum(i for i, v in enumerate(a) if v)``.
+   Equivalent to ``sum(i for i, v in enumerate(a) if v)``.
 
    New in version 3.6