Python中的 Matplotlib.figure.Figure.gca()

Matplotlib是Python中的一个库，它是 NumPy 库的数值数学扩展。 figure 模块提供了顶级 Artist，即 Figure，其中包含所有绘图元素。该模块用于控制所有绘图元素的子图和顶级容器的默认间距。

matplotlib.figure.Figure.gca() 方法

matplotlib 库的 gca() 方法figure 模块用于获取当前坐标轴。

Syntax: gca(self, **kwargs)

Parameters: This method does not accept any parameters.

Returns: This method returns the current axes.

编程需要懂一点英语

下面的示例说明了 matplotlib.figure 中的 matplotlib.figure.Figure.gca()函数：

示例 1：

# Implementation of matplotlib function
import matplotlib.pyplot as plt
import numpy as np
import matplotlib.gridspec as gridspec
from mpl_toolkits.axes_grid1 import make_axes_locatable
   
  
plt.close('all')
arr = np.arange(100).reshape((10, 10))
fig = plt.figure(figsize =(4, 4))
  
im = plt.imshow(arr,
                interpolation ="none",
                cmap ="plasma")
   
divider = make_axes_locatable(fig.gca())
cax = divider.append_axes("left",
                          "15 %", 
                           pad ="30 %")
  
plt.colorbar(im, cax = cax)
   
fig.suptitle('matplotlib.figure.Figure.gca()\
 function Example', fontweight ="bold") 
  
plt.show()

输出：

示例 2：

#Implementation of matplotlib function
import matplotlib.pyplot as plt
from matplotlib.tri import Triangulation
from matplotlib.patches import Polygon
import numpy as np
   
      
ang = 3
radi = 8
radii = np.linspace(0.25, 0.95, radi)
  
res = np.linspace(0, 4 * np.pi, ang)
res = np.repeat(res[..., np.newaxis], radi, axis=1)
res[:, 1::2] += np.pi / ang
  
x = (radii*np.cos(2*res)).flatten()
y = (radii*np.sin(2*res)).flatten()
  
triang = Triangulation(x, y)
triang.set_mask(np.hypot(x[triang.triangles].mean(axis=1),
                         y[triang.triangles].mean(axis=1))
                < 0.25)
     
trifinder = triang.get_trifinder()
     
fig = plt.figure()
plt.triplot(triang, 'go-')
polygon = Polygon([[0, 0], [0, 0]], facecolor='r')
     
def update_polygon(tri):
  
    if tri == -1:
        points = [0, 0, 0]
      
    else:
        points = triang.triangles[tri]
      
    xs = triang.x[points]
    ys = triang.y[points]
    polygon.set_xy(np.column_stack([xs, ys]))
     
     
def motion_notify(event):
      
    if event.inaxes is None:
        tri = -1
      
    else:
        tri = trifinder(event.xdata, event.ydata)
      
    update_polygon(tri)
      
    fig.suptitle('matplotlib.figure.Figure.gca()\
    function Example\n\n Potion number : %i' % tri,
                 fontweight="bold")
      
    event.canvas.draw()
     
update_polygon(-1)
fig.gca().add_patch(polygon)
plt.gcf().canvas.mpl_connect('motion_notify_event',
                             motion_notify)
     
plt.show()

输出：