Matplotlib.axes.Axes.contourf() in Python
Last Updated :
13 Apr, 2020
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.contourf() Function
The Axes.contourf() function in axes module of matplotlib library is also used to plot contours. But contourfdraw filled contours, while contourf draws contour lines.
Syntax:
Axes.contourf(self, *args, data=None, **kwargs)
Parameters: This method accept the following parameters that are described below:
- X, Y: These parameter are the coordinates of the values in Z.
- Z : This parameter is the height values over which the contour is drawn.
- levels : This parameter is used to determine the numbers and positions of the contour lines / regions.
Returns: This returns the following:
- c :This returns the QuadContourSet.
Below examples illustrate the matplotlib.axes.Axes.contourf() function in matplotlib.axes:
Example-1:
import numpy as np
import matplotlib.pyplot as plt
from numpy import ma
from matplotlib import ticker, cm
N = 1000
x = np.linspace( - 6.0 , 6.0 , N)
y = np.linspace( - 7.0 , 7.0 , N)
X, Y = np.meshgrid(x, y)
Z1 = np.exp( - (X) * * 2 - (Y) * * 2 )
z = 50 * Z1
z[: 5 , : 5 ] = - 1
z = ma.masked_where(z < = 0 , z)
fig, ax = plt.subplots()
cs = ax.contourf(X, Y, z, locator = ticker.LogLocator(),
cmap = "Greens" )
cbar = fig.colorbar(cs)
ax.set_title( 'matplotlib.axes.Axes.contourf() Example' )
plt.show()
|
Output:
Example-2:
import matplotlib.pyplot as plt
import numpy as np
x = np.linspace( - 3 , 15 , 450 ).reshape( 1 , - 1 )
y = np.linspace( - 3 , 15 , 720 ).reshape( - 1 , 1 )
z = np.cos(x) * 2 - np.sin(y) * * 2
x, y = x.flatten(), y.flatten()
fig1, ax1 = plt.subplots()
cs = ax1.contourf(x, y, z, hatches = [ '-' , '/' , '\\', ' / / '],
cmap = 'Greens' , extend = 'both' , alpha = 1 )
fig1.colorbar(cs)
ax1.set_title( 'matplotlib.axes.Axes.contourf() Example' )
plt.show()
|
Output:
Like Article
Suggest improvement
Share your thoughts in the comments
Please Login to comment...