DOC Add vector quantization example to KBinsDiscretizer docs (#31613)

pw42020 · StefanieSenger · web-flow · commit adb1ae76d798 · 2025-08-05T14:23:18.000+02:00
Co-authored-by: Stefanie Senger &lt;91849487+StefanieSenger@users.noreply.github.com&gt;
diff --git a/sklearn/preprocessing/_discretization.py b/sklearn/preprocessing/_discretization.py
@@ -179,6 +179,14 @@ class KBinsDiscretizer(TransformerMixin, BaseEstimator):
            [-0.5,  2.5, -2.5, -0.5],
            [ 0.5,  3.5, -1.5,  0.5],
            [ 0.5,  3.5, -1.5,  1.5]])
+
+    While this preprocessing step can be an optimization, it is important
+    to note the array returned by ``inverse_transform`` will have an internal type
+    of ``np.float64`` or ``np.float32``, denoted by the ``dtype`` input argument.
+    This can drastically increase the memory usage of the array. See the
+    :ref:`sphx_glr_auto_examples_cluster_plot_face_compress.py`
+    where `KBinsDescretizer` is used to cluster the image into bins and increases
+    the size of the image by 8x.
     """
 
     _parameter_constraints: dict = {
