3D surface plots in Matplotlib - Mini Project: Build & Apply

3D Surface Plots with Matplotlib

📖 Scenario: You are a data scientist exploring how to visualize three-dimensional data. Imagine you want to show how temperature changes over a flat area depending on two directions: east-west and north-south.

🎯 Goal: You will create a 3D surface plot using matplotlib to visualize a mathematical function that depends on two variables. This will help you understand how to make and display 3D surface plots.

📋 What You'll Learn

Create two 1D arrays for the X and Y coordinates using numpy.linspace.

Create a 2D grid of X and Y values using numpy.meshgrid.

Calculate Z values using a mathematical function of X and Y.

Use matplotlib to create a 3D surface plot.

Display the plot with labels for axes.

💡 Why This Matters

🌍 Real World

3D surface plots help scientists and engineers visualize how a value changes over two directions, like temperature over a landscape or pressure over a wing surface.

💼 Career

Data scientists and analysts use 3D plots to explore complex data and communicate insights clearly to teams and stakeholders.

1

Create X and Y coordinate arrays

Create two variables called x and y using numpy.linspace. Set x to 50 points from -5 to 5, and y to 50 points from -5 to 5.

Matplotlib

import numpy as np
# Create x and y arrays with 50 points from -5 to 5
# Your code here

Need a hint?

Use np.linspace(start, stop, num_points) to create evenly spaced points.

2

Create 2D grid from X and Y

Use numpy.meshgrid with x and y to create two 2D arrays called X and Y.

Matplotlib

import numpy as np

x = np.linspace(-5, 5, 50)
y = np.linspace(-5, 5, 50)
# Create 2D grid arrays X and Y from x and y
# Your code here

Need a hint?

Use X, Y = np.meshgrid(x, y) to create grid arrays.

3

Calculate Z values using a function

Create a variable called Z that calculates np.sin(np.sqrt(X**2 + Y**2)).

Matplotlib

import numpy as np

x = np.linspace(-5, 5, 50)
y = np.linspace(-5, 5, 50)

X, Y = np.meshgrid(x, y)
# Calculate Z as sin of the square root of X squared plus Y squared
# Your code here

Need a hint?

Use np.sin and np.sqrt to calculate Z.

4

Create and display the 3D surface plot

Import matplotlib.pyplot as plt and Axes3D from mpl_toolkits.mplot3d. Create a figure and 3D axes. Use ax.plot_surface(X, Y, Z, cmap='viridis') to plot the surface. Label the X, Y, and Z axes as 'X axis', 'Y axis', and 'Z axis'. Finally, use plt.show() to display the plot.

Matplotlib

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

x = np.linspace(-5, 5, 50)
y = np.linspace(-5, 5, 50)

X, Y = np.meshgrid(x, y)

Z = np.sin(np.sqrt(X**2 + Y**2))

# Create figure and 3D axes
# Plot surface with cmap='viridis'
# Label axes
# Show plot
# Your code here

Need a hint?

Use fig = plt.figure() and ax = fig.add_subplot(111, projection='3d') to create 3D axes.

Use ax.plot_surface to draw the surface.

Label axes with ax.set_xlabel, ax.set_ylabel, and ax.set_zlabel.