---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-1-adec5b1bbfd1> in <module>
      6 pts = mpl.cm.ScalarMappable(norm=norm, cmap=cmap)
      7 pts.set_array([0.1, 0.9])
----> 8 plt.colorbar(pts)

~/rms-python/envs/mpl34/lib/python3.7/site-packages/matplotlib/pyplot.py in colorbar(mappable, cax, ax, **kw)
   2354                                'an image (with imshow) or a contour set ('
   2355                                'with contourf).')
-> 2356     ret = gcf().colorbar(mappable, cax=cax, ax=ax, **kw)
   2357     return ret
   2358

~/rms-python/envs/mpl34/lib/python3.7/site-packages/matplotlib/figure.py in colorbar(self, mappable, cax, ax, use_gridspec, **kw)
   1174                              'panchor']
   1175         cb_kw = {k: v for k, v in kw.items() if k not in NON_COLORBAR_KEYS}
-> 1176         cb = cbar.Colorbar(cax, mappable, **cb_kw)
   1177
   1178         self.sca(current_ax)

~/rms-python/envs/mpl34/lib/python3.7/site-packages/matplotlib/colorbar.py in __init__(self, ax, mappable, **kwargs)
   1170         # even if mappable.draw has not yet been called.
   1171         if mappable.get_array() is not None:
-> 1172             mappable.autoscale_None()
   1173
   1174         self.mappable = mappable

~/rms-python/envs/mpl34/lib/python3.7/site-packages/matplotlib/cm.py in autoscale_None(self)
    474         if self._A is None:
    475             raise TypeError('You must first set_array for mappable')
--> 476         self.norm.autoscale_None(self._A)
    477         self.changed()
    478

~/rms-python/envs/mpl34/lib/python3.7/site-packages/matplotlib/colors.py in autoscale_None(self, A)
   1541     def autoscale_None(self, A):
   1542         # docstring inherited.
-> 1543         super().autoscale_None(np.ma.array(A, mask=(A <= 0)))
   1544
   1545

TypeError: '<=' not supported between instances of 'list' and 'int'