Python Matplotlib：图文本将不会向左对齐

Question

I am trying to get the values for red dots (for values of 'y2') to plot to the left of the dots. I'm using ha='left' but to no avail. I tried the following two aproaches:

for a,b in zip(ind, y2):
    plt.text(a, b, str(b), fontsize=14, color='black', va='center', ha='left)

#OR:
for i, text in enumerate(y2):
    ax.annotate(str(text), (ind[i],y2[i]), ha='left')

Here is the code in its entirety:

import pandas as pd
import numpy as np
from matplotlib import pyplot as plt
%matplotlib inline
df0=pd.read_csv('sample1.csv')

import matplotlib.pyplot as plt

# You typically want your plot to be ~1.33x wider than tall.
# Common sizes: (10, 7.5) and (12, 9)
fig, ax = plt.subplots(1, 1, figsize=(12, 9))
plt.xticks(ind, x_axis, fontsize=14)
#Set y-axis font size
plt.yticks(fontsize=12)
x_axis = ['a','b','c']
y_axis = [2,8,10]

y2 = [3, 5, 9.5]

# Remove the plot frame lines. They are unnecessary here.
ax.spines['top'].set_visible(False)
ax.spines['bottom'].set_visible(False)
ax.spines['right'].set_visible(False)
ax.spines['left'].set_visible(False)

#0 = 'a', 1 = 'b, 2 = 'c'
ind = np.arange(len(x_axis))


#remove axis ticks save for left (y-axis):
plt.tick_params(
    axis='x',          # changes apply to the x-axis
    which='both',      # both major and minor ticks are affected
    bottom='off',      # ticks along the bottom edge are off
    top='off')         # ticks along the top edge are off


plt.tick_params(
    axis='y',          # changes apply to the x-axis
    which='both',      # both major and minor ticks are affected
    right='off')

plt.title('Super Awesome Title Goes Here\n'
          'and Is Continued Here', fontsize=18, va='center')
#Plot dots, cyan circles, no edges, transparency = 0.7 (1 is opaque))
# larger circles
plt.plot(ind, y_axis, 'co', markeredgecolor='none', alpha=1, markersize=40)
#plt.axis(0,10,0,3)

plt.plot(ind, y2, 'ro', markeredgecolor='none', alpha=.7, markersize=40)

#a and b are "where" to plot the label, str(b) is what to plot for the label
#add spaces to put label to the right
for a,b in zip(ind, y_axis):
    plt.text(a, b, "     "+str(b), fontsize=14, color='black', va='center')

for a,b in zip(ind, y2):
    plt.text(a, b, str(b), fontsize=14, color='black', va='center', ha='left')

    #Cell padding between categories
plt.xlim([min(ind) - 0.25, max(ind) + 0.25])
plt.ylim([0, max(y_axis) + 2])
plt.show()

Answer 1

The ha and va arguments specify which edges of the text bounding box will be aligned to the specified x,y coordinates. If you want your text to appear to the left of your dot, you need to align it according to the right hand edge of the bounding box:

from matplotlib import pyplot as  plt

fig, ax = plt.subplots(1, 1)
ax.hold(True)
ax.plot(0, 0, '+', ms=60)
ax.text(0, 0, 'align by top right corner', ha='right', va='top', fontsize=22)
ax.text(0, 0, 'align by bottom left corner', ha='left', va='bottom', fontsize=22)
ax.set_axis_off()
plt.show()