Issue on page /tutorials/W0D3_LinearAlgebra/student/W0D3_Tutorial1.html

[thedannymarsh]

Section 2.1 has an error:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/pyplot.py:197, in _draw_all_if_interactive()
    195 def _draw_all_if_interactive() -> None:
    196     if matplotlib.is_interactive():
--> 197         draw_all()

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/_pylab_helpers.py:132, in Gcf.draw_all(cls, force)
    130 for manager in cls.get_all_fig_managers():
    131     if force or manager.canvas.figure.stale:
--> 132         manager.canvas.draw_idle()

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:1893, in FigureCanvasBase.draw_idle(self, *args, **kwargs)
   1891 if not self._is_idle_drawing:
   1892     with self._idle_draw_cntx():
-> 1893         self.draw(*args, **kwargs)

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:388, in FigureCanvasAgg.draw(self)
    385 # Acquire a lock on the shared font cache.
    386 with (self.toolbar._wait_cursor_for_draw_cm() if self.toolbar
    387       else nullcontext()):
--> 388     self.figure.draw(self.renderer)
    389     # A GUI class may be need to update a window using this draw, so
    390     # don't forget to call the superclass.
    391     super().draw()

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/artist.py:95, in _finalize_rasterization.<locals>.draw_wrapper(artist, renderer, *args, **kwargs)
     93 @wraps(draw)
     94 def draw_wrapper(artist, renderer, *args, **kwargs):
---> 95     result = draw(artist, renderer, *args, **kwargs)
     96     if renderer._rasterizing:
     97         renderer.stop_rasterizing()

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/figure.py:3154, in Figure.draw(self, renderer)
   3151         # ValueError can occur when resizing a window.
   3153 self.patch.draw(renderer)
-> 3154 mimage._draw_list_compositing_images(
   3155     renderer, self, artists, self.suppressComposite)
   3157 for sfig in self.subfigs:
   3158     sfig.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.18/x64/lib/python3.9/site-packages/mpl_toolkits/mplot3d/axes3d.py:472, in Axes3D.draw(self, renderer)
    468 zorder_offset = max(axis.get_zorder()
    469                     for axis in self._axis_map.values()) + 1
    470 collection_zorder = patch_zorder = zorder_offset
--> 472 for artist in sorted(collections_and_patches,
    473                      key=lambda artist: artist.do_3d_projection(),
    474                      reverse=True):
    475     if isinstance(artist, mcoll.Collection):
    476         artist.zorder = collection_zorder

TypeError: '<' not supported between instances of 'NoneType' and 'NoneType'

[N-Heimburger]

This is likely related to the deprecated matplotlib attribute legendHandles - replaced by legend_handles - since the error above is preceded by an AtributeError:

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
Cell In[17], line 27
     24 ax.add_artist(d)
     26 leg = ax.legend([a, b, c, d], ['a', 'b', 'c', 'd'], handlelength = 0, fontsize = 20, loc = 'upper left')
---> 27 for handle, label in zip(leg.legendHandles, leg.texts):
     28   label.set_color(handle.get_facecolor())
     29   handle.set_visible(False)

AttributeError: 'Legend' object has no attribute 'legendHandles'

Running the notebook in Google Collab (defaulting to an earlier version of matplotlib) I get the following:

MatplotlibDeprecationWarning: The legendHandles attribute was deprecated in Matplotlib 3.7 and will be removed two minor releases later. Use legend_handles instead.
  for handle, label in zip(leg.legendHandles, leg.texts):

This also applies to the Python code in Interactive Demo: Linear combination of vectors