Merge pull request matplotlib#23563 from oscargus/line3ddraw

Fix issue with drawing 3D lines where points are from nparray

Author: timhoffm

lib/mpl_toolkits/mplot3d/art3d.py

@@ -171,6 +171,7 @@ def __init__(self, xs, ys, zs, *args, **kwargs):
     def set_3d_properties(self, zs=0, zdir='z'):
         xs = self.get_xdata()
         ys = self.get_ydata()
+        zs = cbook._to_unmasked_float_array(zs).ravel()
         zs = np.broadcast_to(zs, len(xs))
         self._verts3d = juggle_axes(xs, ys, zs, zdir)
         self.stale = True

lib/mpl_toolkits/tests/test_mplot3d.py

@@ -1786,6 +1786,13 @@ def test_text_3d(fig_test, fig_ref):
     assert t3d.get_position_3d() == (0.5, 0.5, 1)
 
 
+def test_draw_single_lines_from_Nx1():
+    # Smoke test for GH#23459
+    fig = plt.figure()
+    ax = fig.add_subplot(projection='3d')
+    ax.plot([[0], [1]], [[0], [1]], [[0], [1]])
+
+
 @check_figures_equal(extensions=["png"])
 def test_pathpatch_3d(fig_test, fig_ref):
     ax = fig_ref.add_subplot(projection="3d")