Generating interactive displays in the Jupyter Notebook

In many situations, information changes dynamically, and it is desirable to present the changes graphically. In this recipe, we will discuss the creation of interacts in the Jupyter Notebook, which can be used to generate dynamic displays based on function evaluations. As an example, we will demonstrate how to create an interactive demonstration of the beats phenomenon from acoustics.

Getting ready

Start Jupyter and run the following three commands in an execution cell:

%matplotlib inline
import numpy as np
import matplotlib.pyplot as plt

How to do it…

We start by defining a function that plots a superposition of waves, with the following code:

xvalues = np.linspace(0, 40, 500)
def plot_function(ratio=0.1):
    plt.figure(figsize=(10,3))
    yvalues = np.cos(2*np.pi*xvalues) + \
              np.cos(2*np.pi*ratio*xvalues)
    plt.plot(xvalues, yvalues, 
             color='green', lw=2)
    plt.axis([0, 40, -2.1, 2.1])
    plt.show()

Calling...