Backport PR matplotlib#27441: Fix some minor issues with hexbin bins …

…argument

galleries/examples/statistics/hexbin_demo.py

@@ -29,7 +29,7 @@
 hb = ax1.hexbin(x, y, gridsize=50, bins='log', cmap='inferno')
 ax1.set(xlim=xlim, ylim=ylim)
 ax1.set_title("With a log color scale")
-cb = fig.colorbar(hb, ax=ax1, label='log10(N)')
+cb = fig.colorbar(hb, ax=ax1, label='counts')
 
 plt.show()
 

lib/matplotlib/axes/_axes.py

@@ -5084,10 +5084,10 @@ def reduce_C_function(C: array) -> float
             )
 
         # Set normalizer if bins is 'log'
-        if bins == 'log':
+        if cbook._str_equal(bins, 'log'):
             if norm is not None:
                 _api.warn_external("Only one of 'bins' and 'norm' arguments "
-                                   f"can be supplied, ignoring bins={bins}")
+                                   f"can be supplied, ignoring {bins=}")
             else:
                 norm = mcolors.LogNorm(vmin=vmin, vmax=vmax)
                 vmin = vmax = None

lib/matplotlib/tests/test_axes.py

@@ -956,17 +956,18 @@ def test_hexbin_extent():
     ax.hexbin("x", "y", extent=[.1, .3, .6, .7], data=data)
 
 
-@image_comparison(['hexbin_empty.png', 'hexbin_empty.png'], remove_text=True)
+@image_comparison(['hexbin_empty.png'], remove_text=True)
 def test_hexbin_empty():
     # From #3886: creating hexbin from empty dataset raises ValueError
     fig, ax = plt.subplots()
     ax.hexbin([], [])
-    fig, ax = plt.subplots()
     # From #23922: creating hexbin with log scaling from empty
     # dataset raises ValueError
     ax.hexbin([], [], bins='log')
     # From #27103: np.max errors when handed empty data
     ax.hexbin([], [], C=[], reduce_C_function=np.max)
+    # No string-comparison warning from NumPy.
+    ax.hexbin([], [], bins=np.arange(10))
 
 
 def test_hexbin_pickable():