Matplotlib.axes.Axes.update_from() in Python

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.update_from() Function

The Axes.update_from() function in axes module of matplotlib library is used to copy properties from other to self.

Syntax: Axes.update_from(self, other)

Parameters: This method accepts any parameters.

• other : This parameter is the property to be updated.

Returns: This method return dictionary of all the properties of the artist.

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

Example 1:

# Implementation of matplotlib function
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.legend_handler import HandlerLine2D


x = np.linspace(0, 3 * np.pi)
y1 = np.sin(x)
y2 = np.cos(x)

fig = plt.figure()

ax = fig.add_subplot(111)
ax.plot(x, y1, c ='b', label ='y1', linewidth = 1.0)
ax.plot(x, y2, c ='g', label ='y2')

linewidth = 7

def update(prop1, prop2):
    prop1.update_from(prop2)
    prop1.set_linewidth(7)

plt.legend(handler_map ={plt.Line2D : HandlerLine2D(update_func = update)})

fig.suptitle('matplotlib.axes.Axes.update_from()\
 function Example', fontweight ="bold")

plt.show()

Output:

Example 2:

# 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.update_from() \
function Example', fontweight ="bold")

plt.show()

Output: