Matplotlib.axes.Axes.get_transform() in Python

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Matplotlib is a library in Python and it is numerical – mathematical extension for NumPy library. The Axes Class contains most of the figure elements: Axis, Tick, Line2D, Text, Polygon, etc., and sets the coordinate system. And the instances of Axes supports callbacks through a callbacks attribute.

matplotlib.axes.Axes.get_transform() Function

The Axes.get_transform() function in axes module of matplotlib library is used to get the Transform instance used by this artist

Syntax: Axes.get_transform(self)

Parameters: This method does not accepts any parameter.

Returns: This method return the Transform instance used by this artist

Below examples illustrate the matplotlib.axes.Axes.get_transform() function in matplotlib.axes:

Example 1:

# Implementation of matplotlib function  
import numpy as np  
import matplotlib.pyplot as plt 
import matplotlib.transforms as mtransforms 
  
  
fig, ax = plt.subplots()  
l1, = ax.plot([0.1, 0.5, 0.9], [0.1, 0.9, 0.5], "bo-") 
l2, = ax.plot([0.1, 0.5, 0.9], [0.5, 0.2, 0.7], "ro-") 
   
for l in [l1, l2]: 
    xx = l.get_xdata() 
    yy = l.get_ydata() 
    shadow, = ax.plot(xx, yy) 
    shadow.update_from(l) 
       
    ot = mtransforms.offset_copy(l.get_transform(), 
                                 ax.figure, 
                                 x = 4.0, y =-6.0, 
                                 units ='points') 
   
    shadow.set_transform(ot) 
    
fig.suptitle('matplotlib.axes.Axes.get_transform() \ 
function Example', fontweight ="bold")  
  
plt.show()  

Output:

Example 2:

# Implementation of matplotlib function   
import matplotlib.pyplot as plt 
from matplotlib import collections, colors, transforms 
import numpy as np 
  
  
nverts = 50
npts = 100
   
r = np.arange(nverts) 
theta = np.linspace(0, 2 * np.pi, nverts) 
  
xx = r * np.sin(theta) 
yy = r * np.cos(theta) 
  
spiral = np.column_stack([xx, yy]) 
   
rs = np.random.RandomState(19680801) 
   
xyo = rs.randn(npts, 2) 
   
colors = [colors.to_rgba(c) 
          for c in plt.rcParams['axes.prop_cycle'].by_key()['color']] 
   
fig, ax1 = plt.subplots() 
   
col = collections.RegularPolyCollection( 
    7, sizes = np.abs(xx) * 10.0,  
    offsets = xyo, 
    transOffset = ax1.transData) 
  
trans = transforms.Affine2D().scale(fig.dpi / 72.0) 
col.set_transform(trans)  
  
ax1.add_collection(col, autolim = True) 
col.set_color(colors) 
  
print("Value Return by get_transform() :\n", 
       col.get_transform()) 
        
fig.suptitle('matplotlib.axes.Axes.get_transform() \ 
function Example', fontweight ="bold")  
  
plt.show()  

Output:

Value Return by get_transform() :
 Affine2D(
    [[1.38888889 0.         0.        ]
     [0.         1.38888889 0.        ]
     [0.         0.         1.        ]])