Fix Axes.hist crash for numpy timedelta64 inputs (#31203)

jayaprajapatii · timhoffm · web-flow · commit c72236701f03 · 2026-03-11T01:40:45.000+01:00
* Fix Axes.hist crash for numpy timedelta64 inputs

* Raise explicit TypeError for numpy.timedelta64 inputs in Axes.hist

* remove duplicate pytest import

* raise TypeError for timedelta64 in Axes.hist and remove bin logic changes

* Handle numpy.timedelta64 and datetime.timedelta explicitly

* fix object check and formatting

* merge timedelta checks and added datetime.timedelta regression tests

* merge timedelta checks and added datetime.timedelta regression test

* fix python style

* Fix indentation

---------

Co-authored-by: Tim Hoffmann &lt;2836374+timhoffm@users.noreply.github.com&gt;
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -7421,6 +7421,15 @@ def hist(self, x, bins=None, range=None, density=False, weights=None,
         x = cbook._reshape_2D(x, 'x')
         nx = len(x)  # number of datasets
 
+        for arr in x:
+            if len(arr) > 0 and isinstance(
+                arr[0], (datetime.timedelta, np.timedelta64)
+            ):
+                raise TypeError(
+                    "Axes.hist does not currently support timedelta inputs. "
+                    "Convert to numeric values  (e.g., .total_seconds()) first."
+                )
+
         # Process unit information.  _process_unit_info sets the unit and
         # converts the first dataset; then we convert each following dataset
         # one at a time.
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -2461,6 +2461,21 @@ def test_hist_log_barstacked():
     assert axs[0].get_ylim() == axs[1].get_ylim()
 
 
+def test_hist_timedelta_raises():
+    import numpy as np
+    import matplotlib.pyplot as plt
+
+    fig, ax = plt.subplots()
+
+    arr_np = np.array([1, 2, 5, 7], dtype="timedelta64[D]")
+    with pytest.raises(TypeError, match="does not currently support timedelta inputs"):
+        ax.hist(arr_np)
+
+    arr_py = [datetime.timedelta(seconds=i) for i in range(5)]
+    with pytest.raises(TypeError, match="does not currently support timedelta inputs"):
+        ax.hist(arr_py)
+
+
 @image_comparison(['hist_bar_empty.png'], remove_text=True)
 def test_hist_bar_empty():
     # From #3886: creating hist from empty dataset raises ValueError
