How do I plot hatched bars using pandas?

I am trying to achieve differentiation by hatch pattern instead of by (just) colour. How do I do it using pandas?

It's possible in matplotlib, by passing the hatch optional argument as discussed here. I know I can also pass that option to a pandas plot, but I don't know how to tell it to use a different hatch pattern for each DataFrame column.

df = pd.DataFrame(rand(10, 4), columns=['a', 'b', 'c', 'd'])
df.plot(kind='bar', hatch='/');

enter image description here

For colours, there is the colormap option described here. Is there something similar for hatching? Or can I maybe set it manually by modifying the Axes object returned by plot?

Solution

Plot the grouped bars with pandas.DataFrame.plot, and then iterate through the bar patches, to add the hatches.

Tested in python 3.11.4, pandas 2.1.0, matplotlib 3.7.2

import pandas as pd

df = pd.DataFrame(np.random.rand(10, 4), columns=['a', 'b', 'c', 'd'])

ax = df.plot(kind='bar', legend=False, figsize=(10, 6), rot=0, width=0.8)

bars = ax.patches
hatches = ''.join(h*len(df) for h in 'x/O.')

for bar, hatch in zip(bars, hatches):
    bar.set_hatch(hatch)

ax.legend(loc='lower center', ncol=4, bbox_to_anchor=(0.5, -0.15))