issue_comments: 1494051039

The reason for the difference in behavior between the two examples is that the first example has named coordinates ('A', 'B', 'C', 'X', 'Y') while the second example has default dimension names ('dim_0', 'dim_1', 'dim_2', 'dim_3', 'dim_4').

In the first example, when calling p.map_dataarray, the x and y arguments are passed as coordinate names ('B' and 'C') instead of dimension names, which is causing the error. The correct way to pass the dimension names would be to use da.dims to get the list of dimension names and pass them as strings:

p.map_dataarray(xr.plot.pcolormesh, y=da.dims[1], x=da.dims[2])

The reason for the difference in behavior between the two examples is that the first example has named coordinates ('A', 'B', 'C', 'X', 'Y') while the second example has default dimension names ('dim_0', 'dim_1', 'dim_2', 'dim_3', 'dim_4').

In the first example, when calling p.map_dataarray, the x and y arguments are passed as coordinate names ('B' and 'C') instead of dimension names, which is causing the error. The correct way to pass the dimension names would be to use da.dims to get the list of dimension names and pass them as strings:

p.map_dataarray(xr.plot.pcolormesh, y=da.dims[1], x=da.dims[2])

In the second example, the error message is more informative because the dimension names are already being used. The error message indicates that the valid options for the x argument are None, 'dim_3', and 'dim_4', which are the dimensions with index 3 and 4 in the data array. The correct way to pass the dimension names would be:

p.map_dataarray(xr.plot.pcolormesh, y='dim_1', x='dim_2') This will map the pcolormesh plot onto the dimensions 'dim_1' and 'dim_2', which correspond to the columns and rows of the contour plot.