在下面的图中，我想去掉一个特定的ticklabel：

下面是生成图像的代码：

from matplotlib import pyplot as plt
import numpy as np

x = np.linspace(-6, 6, 600)
def sigmoid(x):
    return 1/(1+np.exp(-x))
y = sigmoid(x)
fig, ax = plt.subplots(figsize=(3,3), dpi=300)

# Move left y-axis and bottom x-axis to centre, passing through (0,0)
ax.spines['left'].set_position('zero')
ax.spines['bottom'].set_position('zero')

# Eliminate upper and right axes
ax.spines['right'].set_color('none')
ax.spines['top'].set_color('none')

# Show ticks in the left and lower axes only
ax.xaxis.set_ticks_position('bottom')
ax.yaxis.set_ticks_position('left')

# Set axis range
ax.set_xlim(-6, 6)
# ax.set_ylim(-2, 2)

# Set axis labels
ax.set_xlabel(r"$x$", loc='right')
ax.set_ylabel(r"sigmoid$(x)$", loc='top')

# Set axes facecolor
ax.set_facecolor('none')

print(ax.get_yticklabels())
ax.plot(x,y)
print(ax.get_yticklabels())

plt.show()

然后在plt.plot(x,y)之前得到以下yticklabels：

[Text(0, 0.0, '0.0'), Text(0, 0.2, '0.2'), Text(0, 0.4, '0.4'), Text(0, 0.6000000000000001, '0.6'), Text(0, 0.8, '0.8'), Text(0, 1.0, '1.0')]

plt.plot(x,y)之后的这些

[Text(0, -0.2, '−0.2'), Text(0, 0.0, '0.0'), Text(0, 0.2, '0.2'), Text(0, 0.4000000000000001, '0.4'), Text(0, 0.6000000000000001, '0.6'), Text(0, 0.8, '0.8'), Text(0, 1.0000000000000002, '1.0'), Text(0, 1.2000000000000002, '1.2')

我的想法是使用如下代码更改标签：

ylabels = ax.get_yticklabels()
for lbl in ylabels:
    lbl_txt = lbl.get_text().replace('−', '-') # replace U+2212 with normal '-' (U+002d)
    if float(lbl_txt) == 0.:
        lbl.set_text('')
ylabels = ax.get_yticklabels()
ax.set_yticklabels(ylabels)

但是，并且代码成功地替换了'0。'0'标签与空字符串，但图形看起来相同。另外，为什么返回的yticklabels比图中显示的多两个？