Composite coordinate plot only works in one orientation #788
Description
When I create a composite coordinate i.e. d.coords['c'] = d.a * d.b and then try and plot a 2d plot of the data, it only works when the composite index is on the y axis. When on the x-axis it fails with
TypeError: Dimensions of C (3, 5) are incompatible with X (4) and/or Y (6)
ipynb notebook (and pdf version of same notebook) attached that recreate the error
xarray composite coord plot.pdf
xarray composite coord plot.ipynb.zip