How to control the order of facet gird rows and/or columns in xarray?

Question

I am trying to change the order of variables I use to make a facet grid in xarray. For example, I have [a,b,c,d] as column names. I want to reorder it to [c,d,a,b]. Unfortunately, unlike seaborn, I could not find parameters such as col_order or row_order in xarray plot function (

https://xarray.pydata.org/en/stable/generated/xarray.plot.FacetGrid.html

Update: To help myself better explain what I need, I took the example below from the user guide of xarray: In the following example, I need to change the place of months. I mean, for example, I want to put the month 7 as the first column and 2nd month as the 5th and so on and so forth.

import matplotlib as mpl
import matplotlib.pyplot as plt
import numpy as np
import xarray as xr
ds = xr.tutorial.open_dataset("air_temperature.nc").rename({"air": "Tair"})

# we will add a gradient field with appropriate attributes
ds["dTdx"] = ds.Tair.differentiate("lon") / 110e3 / np.cos(ds.lat * np.pi / 180)
ds["dTdy"] = ds.Tair.differentiate("lat") / 105e3
ds.dTdx.attrs = {"long_name": "$∂T/∂x$", "units": "°C/m"}
ds.dTdy.attrs = {"long_name": "$∂T/∂y$", "units": "°C/m"}
monthly_means = ds.groupby("time.month").mean()
# xarray's groupby reductions drop attributes. Let's assign them back so we get nice labels.
monthly_means.Tair.attrs = ds.Tair.attrs
fg = monthly_means.Tair.plot(
    col="month",
    col_wrap=4,  # each row has a maximum of 4 columns
)
plt.show()

Any help is highly appreciated.

Answer 1

xarray will respect the shape of your data, so you can rearrange the data prior to plotting:

In [2]: ds = xr.tutorial.open_dataset("air_temperature.nc")

In [3]: ds_mon = ds.groupby("time.month").mean()

In [4]: # order the data by month, descending
   ...: ds_mon.air.sel(month=list(range(12, 0, -1))).plot(
   ...:     col="month", col_wrap=4,
   ...: )

Out[4]: <xarray.plot.facetgrid.FacetGrid at 0x16b9a7700>