Machine Learning for OpenCV 4 - Second Edition

Producing a simple plot

Without further ado, let's create our first plot.

Let's say that we want to produce a simple line plot of the sine function, sin(x). We want the function to be evaluated at all points on the x axis where 0 < x < 10. We will use NumPy's linspace function to create a linear spacing on the x axis, from x values 0 to 10, and a total of 100 sampling points:

In [3]: import numpy as npIn [4]: x = np.linspace(0, 10, 100)

We can evaluate the sin function at all points, x, using NumPy's sin function, and visualize the result by calling the plot function of plt:

In [5]: plt.plot(x, np.sin(x))

Did you try it yourself? What happened? Did anything show up?

The thing is, depending on where you are running this script, you might not ...