Can't plot legend of different kind of lines #265
Description
Description
If multiple kinds of line are plotted on the figure, the legend() doesn't work.
Steps to reproduce
import proplot as pplt
import numpy as np
state = np.random.RandomState(51423)
data = (state.rand(10, 5) - 0.5).cumsum(axis=0)
fig, axs = pplt.subplots()
data = state.rand(20)
l1 = axs.plot(data, label='l1')
l2 = axs.plot(data*2, label='l2')
l3 = axs.axhline(0.5, c='green', label='l3')
axs.legend([l1, l2, l3], loc='r')Expected behavior
proplot 0.6.4 works well:
Actual behavior
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
/tmp/ipykernel_31462/545939102.py in <module>
11 l3 = axs.axhline(0.5, c='green', label='l3')
12 # axs.legend([l1, l2], loc='r')
---> 13 axs.legend([l1, l2, l3], loc='r')
~/new/miniconda3/envs/pyresample_min/lib/python3.8/site-packages/proplot/ui.py in _iterator(*args, **kwargs)
780 result = []
781 for func in objs:
--> 782 result.append(func(*args, **kwargs))
783 if len(self) == 1:
784 return result[0]
~/new/miniconda3/envs/pyresample_min/lib/python3.8/site-packages/proplot/axes/base.py in legend(self, handles, labels, loc, width, space, queue, **kwargs)
1869 if loc in ('left', 'right', 'top', 'bottom'):
1870 ax = self.panel_axes(loc, width=width, space=space, filled=True)
-> 1871 obj = ax.legend(handles, labels, loc='fill', **kwargs)
1872 self._add_colorbar_legend(loc, obj, legend=True) # add to *this* axes
1873 return obj
~/new/miniconda3/envs/pyresample_min/lib/python3.8/site-packages/proplot/axes/base.py in legend(self, handles, labels, loc, width, space, queue, **kwargs)
1895
1896 # Generate legend
-> 1897 obj = wrap.legend_extras(self, handles, labels, loc=loc, **kwargs)
1898 self._add_colorbar_legend(loc, obj, legend=True) # possibly replace another
1899 return obj
~/new/miniconda3/envs/pyresample_min/lib/python3.8/site-packages/proplot/axes/plot.py in legend_extras(self, handles, labels, loc, ncol, ncols, center, order, label, title, fontsize, fontweight, fontcolor, color, marker, lw, linewidth, dashes, linestyle, markersize, frameon, frame, **kwargs)
4344 if list_of_lists:
4345 if any(not np.iterable(_) for _ in handles):
-> 4346 raise ValueError(f'Invalid handles={handles!r}.')
4347 if not labels:
4348 labels = [None] * len(handles)
ValueError: Invalid handles=[[<matplotlib.lines.Line2D object at 0x7ffacb87cfd0>], [<matplotlib.lines.Line2D object at 0x7ffacb87cca0>], <matplotlib.lines.Line2D object at 0x7ffa42564d90>].
Proplot version
matplotlib: 3.3.4
proplot: 0.7.0