Trying to place text in mpl just above the first yticklabel-CodePudding

I am having diffculties to move the text "Rank" exactly one line above the first label and by not using guesswork as I have different chart types with variable sizes, widths and also paddings between the labels and bars.

import matplotlib.pyplot as plt
import pandas as pd
import numpy as np
from pylab import rcParams

rcParams['figure.figsize'] = 8, 6
fig = plt.figure()
ax = fig.add_subplot(1, 1, 1)
df = pd.DataFrame.from_records(zip(np.arange(1,30)))
df.plot.barh(width=0.8,ax=ax,legend=False)
ax.spines['right'].set_visible(False)
ax.spines['top'].set_visible(False)
ax.spines['left'].set_visible(False)
ax.spines['bottom'].set_visible(False)
ax.tick_params(left=False, bottom=False)
ax.tick_params(axis='y', which='major', pad=36)
ax.set_title("Rankings")
ax.text(-5,30,"Rank")

plt.show()

Using transData.transform didn't get me any further. The problem seems to be that ax.text() with the position params of (0,0) aligns with the start of the bars and not the yticklabels which I need, so getting the exact position of yticklabels relative to the axis would be helpful.

CodePudding user response：

The following approach creates an

CodePudding user response：

I've answered my own question while Johan was had posted his one - which is pretty good and what I wanted. However, I post mine anyways as it uses an entirely different approach. Here I add a "ghost" row into the dataframe and label it appropriately which solves the problem:

import matplotlib.pyplot as plt
import pandas as pd
import numpy as np
from pylab import rcParams

rcParams['figure.figsize'] = 8, 6
fig = plt.figure()
ax = fig.add_subplot(1, 1, 1)
df = pd.DataFrame.from_records(zip(np.arange(1,30)),columns=["val"])

#add a temporary header
new_row = pd.DataFrame({"val":0}, index=[0])
df = pd.concat([df[:],new_row]).reset_index(drop = True)

df.plot.barh(width=0.8,ax=ax,legend=False)
ax.spines['right'].set_visible(False)
ax.spines['top'].set_visible(False)
ax.spines['left'].set_visible(False)
ax.spines['bottom'].set_visible(False)
ax.tick_params(left=False, bottom=False)
ax.tick_params(axis='y', which='major', pad=36)
ax.set_title("Rankings")

# Set the top label to "Rank"
yticklabels = [t for t in ax.get_yticklabels()]
yticklabels[-1]="Rank"

# Left align all labels
[t.set_ha("left") for t in ax.get_yticklabels()]
ax.set_yticklabels(yticklabels)

# delete the top bar effectively by setting it's height to 0
ax.patches[-1].set_height(0)

plt.show()

Perhaps the advantage is that it is always a constant distance above the top label, but with the disadvantage that this is a bit "patchy" in the most literal sense to transform your dataframe for this task.