DOC ensure sklearn/utils/extmath/stable_cumsum passes numpydoc (#24348)

TheDevPanda · web-flow · commit 45756377c748 · 2022-09-04T09:55:01.000+02:00
diff --git a/sklearn/tests/test_docstrings.py b/sklearn/tests/test_docstrings.py
@@ -34,7 +34,6 @@
     "sklearn.utils.extmath.randomized_svd",
     "sklearn.utils.extmath.safe_sparse_dot",
     "sklearn.utils.extmath.squared_norm",
-    "sklearn.utils.extmath.stable_cumsum",
     "sklearn.utils.extmath.svd_flip",
     "sklearn.utils.extmath.weighted_mode",
     "sklearn.utils.fixes.delayed",
diff --git a/sklearn/utils/extmath.py b/sklearn/utils/extmath.py
@@ -1057,6 +1057,9 @@ def _deterministic_vector_sign_flip(u):
 def stable_cumsum(arr, axis=None, rtol=1e-05, atol=1e-08):
     """Use high precision for cumsum and check that final value matches sum.
 
+    Warns if the final cumulative sum does not match the sum (up to the chosen
+    tolerance).
+
     Parameters
     ----------
     arr : array-like
@@ -1068,6 +1071,11 @@ def stable_cumsum(arr, axis=None, rtol=1e-05, atol=1e-08):
         Relative tolerance, see ``np.allclose``.
     atol : float, default=1e-08
         Absolute tolerance, see ``np.allclose``.
+
+    Returns
+    -------
+    out : ndarray
+        Array with the cumulative sums along the chosen axis.
     """
     out = np.cumsum(arr, axis=axis, dtype=np.float64)
     expected = np.sum(arr, axis=axis, dtype=np.float64)
