Display Minor Ticks and Major Ticks at the Same Axis Location

Question

I have a plot with both Major and Minor Ticks. It is a grouped bar chart and I don't want the legend describing each category, but want each category shown in the minor ticks. Then I want each group to have the name in the major ticks.

I can do this to some extent, but the major tick seems to override the minor tick at the same location. How can I turn this off?

import pandas as pd
import matplotlib.pyplot as plt

df = pd.DataFrame(
    {
        0: [84, 41],
        1: [0, 0],
        2: [18.5, 3.5],
        3: [65.5, 124],
        4: [0.5, 0]
    },
    index = ['A', 'B']
)

ax = df.plot.bar(
    rot=0,
    legend=False,
    color=['gray', 'red', 'green', 'lightblue', 'darkblue',],
)

labels = df.unstack().index
label_x, label_mode = [], []

for rect, idx in zip(ax.patches, labels):
    print(rect, idx)
    label_mode.append(idx[0])
    label_x.append(rect.xy[0] + (rect.get_width() * 0.5))

ax.set_xticklabels(['A', 'B'])
ax.set_xticks(label_x, minor=True)
ax.set_xticklabels(label_mode, minor=True)
ax.tick_params(axis='x', which='minor', length=0)

ax.tick_params(axis='x', which='major', length=10, width=0)

Answer 1

This was actually very simple. It is a single parameter remove_overlapping_locs passed to xaxis object.

ax.xaxis.remove_overlapping_locs = False

See matplotlib API changes 3.1.0 for more details.