Saving animations (GIF, MP4) in Matplotlib - Mini Project: Build & Apply

Saving animations (GIF, MP4)

📖 Scenario: You are creating a simple animated plot to show how a sine wave changes over time. You want to save this animation as both a GIF and an MP4 file so you can share it easily.

🎯 Goal: Build a Python script using matplotlib to create a sine wave animation and save it as a GIF and MP4 file.

📋 What You'll Learn

Create a time series data for the sine wave.

Set up the animation function using matplotlib.

Save the animation as a GIF file.

Save the animation as an MP4 file.

💡 Why This Matters

🌍 Real World

Animations help visualize changes over time in data, useful in science, engineering, and education.

💼 Career

Knowing how to create and save animations is valuable for data scientists and analysts who present dynamic data insights.

1

Create the sine wave data

Import numpy as np and matplotlib.pyplot as plt. Then create a numpy array called x with 100 points from 0 to 2π using np.linspace(0, 2 * np.pi, 100).

Matplotlib

import numpy as np
import matplotlib.pyplot as plt
# Create the x values for the sine wave
# Your code here

Need a hint?

Use np.linspace to create evenly spaced points between 0 and 2π.

2

Set up the animation configuration

Create a figure and axis using plt.subplots() and assign them to variables fig and ax. Then create a line object using ax.plot with initial empty data and assign it to line.

Matplotlib

import numpy as np
import matplotlib.pyplot as plt
x = np.linspace(0, 2 * np.pi, 100)

fig, ax = plt.subplots()
# Create an empty line object on ax
# Your code here

Need a hint?

Use ax.plot([], []) to create an empty line that will be updated in the animation.

3

Create the animation function

Import FuncAnimation from matplotlib.animation. Define a function called update that takes a frame number i and updates the line data to show y = np.sin(x + i / 10). Then create an animation object called ani using FuncAnimation with fig, update, and frames=100.

Matplotlib

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation

x = np.linspace(0, 2 * np.pi, 100)
fig, ax = plt.subplots()
line, = ax.plot([], [])

def update(i):
    # Update the line data for frame i
    # Your code here

ani = FuncAnimation(fig, update, frames=100)

Need a hint?

The update function changes the y-values of the line for each frame.

4

Save the animation as GIF and MP4

Save the animation ani as a GIF file named animation.gif using ani.save with writer='pillow'. Then save the same animation as an MP4 file named animation.mp4 using ani.save with writer='ffmpeg'. Finally, print 'Saved animation.gif and animation.mp4'.

Matplotlib

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation

x = np.linspace(0, 2 * np.pi, 100)
fig, ax = plt.subplots()
line, = ax.plot([], [])

def update(i):
    y = np.sin(x + i / 10)
    line.set_data(x, y)
    return line,

ani = FuncAnimation(fig, update, frames=100)

# Save the animation as GIF and MP4
# Your code here

Need a hint?

Use ani.save('filename', writer='pillow') for GIF and ani.save('filename', writer='ffmpeg') for MP4.