Python中的 Matplotlib.axes.Axes.get_ylabel()

Matplotlib是Python中的一个库，它是 NumPy 库的数值数学扩展。 Axes 类包含大部分图形元素：Axis、Tick、Line2D、Text、Polygon 等，并设置坐标系。 Axes 的实例通过回调属性支持回调。

matplotlib.axes.Axes.get_ylabel()函数

matplotlib 库的 axes 模块中的Axes.get_ylabel()函数用于获取 ylabel 文本字符串。

Syntax: Axes.get_ylabel(self)

Parameters: This method does not accepts any parameters.

Return: This function return the ylabel text string.

下面的示例说明了 matplotlib.axes 中的 matplotlib.axes.Axes.get_ylabel()函数：

示例 1：

import matplotlib.pyplot as plt
import numpy as np
    
t = np.arange(0.01, 5.0, 0.01)
s = np.exp(-t)
    
fig, ax = plt.subplots()
    
ax.plot(t, s)
ax.set_ylim(1, 0)
ax.set_ylabel('Display Y-axis Label', fontweight ='bold')
ax.grid(True)
   
w = ax.get_ylabel()
ax.set_ylabel("")
ax.text(1.5, 0.58, "Previously assigned Y-Label : \n\n"+str(w),
       fontsize = 12)
fig.suptitle("matplotlib.axes.Axes.get_ylabel() function\
 Example\n", fontweight ="bold")
plt.show()

输出：

示例 2：

# Implementation of matplotlib function
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.cbook as cbook
   
with cbook.get_sample_data('goog.npz') as datafile:
    price_data = np.load(datafile)['price_data'].view(np.recarray)
price_data = price_data[-250:]  # get the most recent 250 trading days
   
delta1 = np.diff(price_data.adj_close) / price_data.adj_close[:-1]
   
volume = (25 * price_data.volume[:-2] / price_data.volume[0])**(2.2)
close = (0.03 * price_data.close[:-2] / 0.03 * price_data.open[:-2])**2
   
fig, ax = plt.subplots()
ax.scatter(delta1[:-1], delta1[1:], 
           c = close, s = volume, 
           alpha = 0.5)
   
ax.set_ylabel(r'Y-axis contains $\Delta_{i + 1}$ values',
              fontweight ='bold')
ax.grid(True)
  
w = ax.get_ylabel()
ax.set_ylabel("")
ax.set_xlabel(w)
ax.text(-0.1, 0.1, "Previously assigned Y-Label is now Assigned\
to X-Label", fontsize = 12, fontweight ="bold")
  
fig.suptitle("matplotlib.axes.Axes.get_ylabel() function \
Example\n", fontweight ="bold")
plt.show()

输出：