How to change angle of 3D plot in Python?
Prerequisites: Matplotlib, NumPy
In this article, we will see how can we can view our graph from different angles, Here we use three different methods to plot our graph. Before starting let’s see some basic concepts of the required module for this objective.
- Matplotlib is a multi-platform data visualization library built on NumPy arrays and designed to work with the broader SciPy stack
- Numpy is a general-purpose array-processing package. It provides a high-performance multidimensional array object, and tools for working with these arrays. It is the fundamental package for scientific computing with Python
- mpl_toolkits provides some basic 3D plotting (scatter, surf, line, mesh) tools.
Approach:
- Import required library.
- Create a figure.
- Create a datasheet.
- Change angle of the 3D plot
- Show Graph.
Step 1: Import libraries.
Python3
from mpl_toolkits import mplot3d import numpy as np import matplotlib.pyplot as plt |
Step 2: Plotting 3-D axis figure.
Python3
from mpl_toolkits import mplot3d import numpy as np import matplotlib.pyplot as plt fig = plt.figure(figsize = (8, 8)) ax = plt.axes(projection = '3d') |
Step 3: Creating a Datasheet for all the 3-axis of the sample.
Python3
from mpl_toolkits import mplot3d import numpy as np import matplotlib.pyplot as plt fig = plt.figure(figsize = (8, 8)) ax = plt.axes(projection = '3d') # Data for a three-dimensional line z = np.linspace(0, 15, 1000) x = np.sin(z) y = np.cos(z) ax.plot3D(x, y, z, 'green') |
Step 4: Use view_init() can be used to rotate the axes programmatically.
Syntax: view_init(elev, azim)
Parameters:
- ‘elev’ stores the elevation angle in the z plane.
- ‘azim’ stores the azimuth angle in the x,y plane.D constructor.
Python3
from mpl_toolkits import mplot3d import numpy as np import matplotlib.pyplot as plt fig = plt.figure(figsize = (8,8)) ax = plt.axes(projection = '3d') # Data for a three-dimensional line z = np.linspace(0, 15, 1000) x = np.sin(z) y = np.cos(z) ax.plot3D(x, y, z, 'green') ax.view_init(-140, 60) |
Below is the full Implementation:
Example 1: In this example, we will plot a curve graph with an elevated angle of -140 degrees and a horizontal angle of 60 degrees.
Python3
from mpl_toolkits import mplot3d import numpy as np import matplotlib.pyplot as plt fig = plt.figure(figsize = (8,8)) ax = plt.axes(projection = '3d') # Data for a three-dimensional line z = np.linspace(0, 15, 1000) x = np.sin(z) y = np.cos(z) ax.plot3D(x, y, z, 'green') ax.view_init(-140, 60) plt.show() |
Output:
Example 2: In this example, we will plot a curve graph with an elevated angle of 120 degrees and a horizontal angle of 30 degrees.
Python3
from mpl_toolkits import mplot3d import numpy as np import matplotlib.pyplot as plt fig = plt.figure(figsize = (8, 8)) ax = plt.axes(projection = '3d') # Data for a three-dimensional line z = np.linspace(0, 15, 1000) x = np.sin(z) y = np.cos(z) ax.plot3D(x, y, z, 'green') ax.view_init(120, 30) plt.show() |
Output:
Example 3: In this example, we will plot a rectangular plate graph with an angle view of 50 degrees.
Python3
import numpy as np from matplotlib import pyplot as plt from mpl_toolkits.mplot3d import Axes3D from math import sin, cos fig = plt.figure(figsize = (8,8)) ax = fig.add_subplot(111, projection = '3d') #creating Datasheet y = np.linspace(-1, 1, 200) x = np.linspace(-1, 1, 200) x,y = np.meshgrid(x, y) #set z values z = x + y # rotate the samples by changing the value of 'a' a = 50 t = np.transpose(np.array([x, y, z]), ( 1, 2, 0)) m = [[cos(a), 0, sin(a)],[0, 1, 0], [-sin(a), 0, cos(a)]] X,Y,Z = np.transpose(np.dot(t, m), (2, 0, 1)) #label axes ax.set_xlabel('X') ax.set_ylabel('Y') ax.set_zlabel('Z') #plot figure ax.plot_surface(X,Y,Z, alpha = 0.5, color = 'red') plt.show() |
Output:
