Animation in iPython notebook

Some options you have for animating plots in Jupyter/IPython, using matplotlib:

  • Using display in a loop Use IPython.display.display(fig) to display a figure in the output. Using a loop you would want to clear the output before a new figure is shown. Note that this technique gives in general not so smooth resluts. I would hence advice to use any of the below.

    import matplotlib.pyplot as plt
    import matplotlib.animation
    import numpy as np
    from IPython.display import display, clear_output
    
    t = np.linspace(0,2*np.pi)
    x = np.sin(t)
    
    fig, ax = plt.subplots()
    l, = ax.plot([0,2*np.pi],[-1,1])
    
    animate = lambda i: l.set_data(t[:i], x[:i])
    
    for i in range(len(x)):
        animate(i)
        clear_output(wait=True)
        display(fig)
        
    plt.show()
  • %matplotlib notebook Use IPython magic %matplotlib notebook to set the backend to the notebook backend. This will keep the figure alive instead of displaying a static png file and can hence also show animations.
    Complete example:

    %matplotlib notebook
    import matplotlib.pyplot as plt
    import matplotlib.animation
    import numpy as np
    
    t = np.linspace(0,2*np.pi)
    x = np.sin(t)
    
    fig, ax = plt.subplots()
    l, = ax.plot([0,2*np.pi],[-1,1])
    
    animate = lambda i: l.set_data(t[:i], x[:i])
    
    ani = matplotlib.animation.FuncAnimation(fig, animate, frames=len(t))
    
    plt.show()
  • %matplotlib tk Use IPython magic %matplotlib tk to set the backend to the tk backend. This will open the figure in a new plotting window, which is interactive and can thus also show animations.
    Complete example:

    %matplotlib tk
    import matplotlib.pyplot as plt
    import matplotlib.animation
    import numpy as np
    
    t = np.linspace(0,2*np.pi)
    x = np.sin(t)
    
    fig, ax = plt.subplots()
    l, = ax.plot([0,2*np.pi],[-1,1])
    
    animate = lambda i: l.set_data(t[:i], x[:i])
    
    ani = matplotlib.animation.FuncAnimation(fig, animate, frames=len(t))
    
    plt.show()
  • Convert animation to mp4 video (option mentionned by @Perfi already):

    from IPython.display import HTML
    HTML(ani.to_html5_video())
    

    or use plt.rcParams["animation.html"] = "html5" at the beginning of the notebook.
    This will require to have ffmpeg video codecs available to convert to HTML5 video. The video is then shown inline. This is therefore compatible with %matplotlib inline backend. Complete example:

    %matplotlib inline
    import matplotlib.pyplot as plt
    plt.rcParams["animation.html"] = "html5"
    import matplotlib.animation
    import numpy as np
    
    t = np.linspace(0,2*np.pi)
    x = np.sin(t)
    
    fig, ax = plt.subplots()
    l, = ax.plot([0,2*np.pi],[-1,1])
    
    animate = lambda i: l.set_data(t[:i], x[:i])
    
    ani = matplotlib.animation.FuncAnimation(fig, animate, frames=len(t))
    ani
    %matplotlib inline
    import matplotlib.pyplot as plt
    import matplotlib.animation
    import numpy as np
    
    t = np.linspace(0,2*np.pi)
    x = np.sin(t)
    
    fig, ax = plt.subplots()
    l, = ax.plot([0,2*np.pi],[-1,1])
    
    animate = lambda i: l.set_data(t[:i], x[:i])
    
    ani = matplotlib.animation.FuncAnimation(fig, animate, frames=len(t))
    
    from IPython.display import HTML
    HTML(ani.to_html5_video())
  • Convert animation to JavaScript:

    from IPython.display import HTML
    HTML(ani.to_jshtml())
    

    or use plt.rcParams["animation.html"] = "jshtml" at the beginning of the notebook.
    This will display the animation as HTML with JavaScript. This highly compatible with most new browsers and also with the %matplotlib inline backend. It is available in matplotlib 2.1 or higher.
    Complete example:

    %matplotlib inline
    import matplotlib.pyplot as plt
    plt.rcParams["animation.html"] = "jshtml"
    import matplotlib.animation
    import numpy as np
    
    t = np.linspace(0,2*np.pi)
    x = np.sin(t)
    
    fig, ax = plt.subplots()
    l, = ax.plot([0,2*np.pi],[-1,1])
    
    animate = lambda i: l.set_data(t[:i], x[:i])
    
    ani = matplotlib.animation.FuncAnimation(fig, animate, frames=len(t))
    ani
    %matplotlib inline
    import matplotlib.pyplot as plt
    import matplotlib.animation
    import numpy as np
    
    t = np.linspace(0,2*np.pi)
    x = np.sin(t)
    
    fig, ax = plt.subplots()
    l, = ax.plot([0,2*np.pi],[-1,1])
    
    animate = lambda i: l.set_data(t[:i], x[:i])
    
    ani = matplotlib.animation.FuncAnimation(fig, animate, frames=len(t))
    
    from IPython.display import HTML
    HTML(ani.to_jshtml())

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