Fix the error- TypeError: 'float' object is not iterable (matplotlib#22710)

Co-authored-by: Thomas A Caswell <[email protected]>

Author: kjain

lib/matplotlib/axis.py

@@ -1825,8 +1825,11 @@ def set_ticklabels(self, ticklabels, *, minor=False, **kwargs):
             For each tick, includes ``tick.label1`` if it is visible, then
             ``tick.label2`` if it is visible, in that order.
         """
-        ticklabels = [t.get_text() if hasattr(t, 'get_text') else t
-                      for t in ticklabels]
+        try:
+            ticklabels = [t.get_text() if hasattr(t, 'get_text') else t
+                          for t in ticklabels]
+        except TypeError:
+            raise TypeError(f"{ticklabels:=} must be a sequence") from None
         locator = (self.get_minor_locator() if minor
                    else self.get_major_locator())
         if isinstance(locator, mticker.FixedLocator):

lib/matplotlib/tests/test_axes.py

@@ -5390,6 +5390,15 @@ def test_set_ticks_with_labels(fig_test, fig_ref):
     ax.set_yticks([2, 4], ['A', 'B'], minor=True)
 
 
+def test_set_noniterable_ticklabels():
+    # Ensure a useful TypeError message is raised
+    # when given a non-iterable ticklabels argument
+    # Pull request #22710
+    with pytest.raises(TypeError, match='must be a sequence'):
+        fig, ax = plt.subplots(2)
+        ax[1].set_xticks([2, 9], 3.1)
+
+
 def test_subsampled_ticklabels():
     # test issue 11937
     fig, ax = plt.subplots()