Merge pull request matplotlib#23333 from anntzer/en

Fix errorbar handling of nan.

Author: tacaswell

lib/matplotlib/axes/_axes.py

@@ -1083,13 +1083,14 @@ def hlines(self, y, xmin, xmax, colors=None, linestyles='solid',
         lines._internal_update(kwargs)
 
         if len(y) > 0:
-            minx = min(np.nanmin(xmin), np.nanmin(xmax))
-            maxx = max(np.nanmax(xmin), np.nanmax(xmax))
-            miny = np.nanmin(y)
-            maxy = np.nanmax(y)
-
+            # Extreme values of xmin/xmax/y.  Using masked_verts here handles
+            # the case of y being a masked *object* array (as can be generated
+            # e.g. by errorbar()), which would make nanmin/nanmax stumble.
+            minx = np.nanmin(masked_verts[..., 0])
+            maxx = np.nanmax(masked_verts[..., 0])
+            miny = np.nanmin(masked_verts[..., 1])
+            maxy = np.nanmax(masked_verts[..., 1])
             corners = (minx, miny), (maxx, maxy)
-
             self.update_datalim(corners)
             self._request_autoscale_view()
 
@@ -1162,11 +1163,13 @@ def vlines(self, x, ymin, ymax, colors=None, linestyles='solid',
         lines._internal_update(kwargs)
 
         if len(x) > 0:
-            minx = np.nanmin(x)
-            maxx = np.nanmax(x)
-            miny = min(np.nanmin(ymin), np.nanmin(ymax))
-            maxy = max(np.nanmax(ymin), np.nanmax(ymax))
-
+            # Extreme values of x/ymin/ymax.  Using masked_verts here handles
+            # the case of x being a masked *object* array (as can be generated
+            # e.g. by errorbar()), which would make nanmin/nanmax stumble.
+            minx = np.nanmin(masked_verts[..., 0])
+            maxx = np.nanmax(masked_verts[..., 0])
+            miny = np.nanmin(masked_verts[..., 1])
+            maxy = np.nanmax(masked_verts[..., 1])
             corners = (minx, miny), (maxx, maxy)
             self.update_datalim(corners)
             self._request_autoscale_view()

lib/matplotlib/tests/test_axes.py

@@ -3790,6 +3790,20 @@ def test_errorbar_linewidth_type(elinewidth):
     plt.errorbar([1, 2, 3], [1, 2, 3], yerr=[1, 2, 3], elinewidth=elinewidth)
 
 
+@check_figures_equal(extensions=["png"])
+def test_errorbar_nan(fig_test, fig_ref):
+    ax = fig_test.add_subplot()
+    xs = range(5)
+    ys = np.array([1, 2, np.nan, np.nan, 3])
+    es = np.array([4, 5, np.nan, np.nan, 6])
+    ax.errorbar(xs, ys, es)
+    ax = fig_ref.add_subplot()
+    ys = np.array([1, 2, np.nan, np.nan, 3])
+    es = np.array([4, 5, np.nan, np.nan, 6])
+    ax.errorbar([0, 1], [1, 2], [4, 5])
+    ax.errorbar([4], [3], [6], fmt="C0")
+
+
 @image_comparison(['hist_stacked_stepfilled', 'hist_stacked_stepfilled'])
 def test_hist_stacked_stepfilled():
     # make some data