Python Data Visualization Cookbook - Second Edition

Drawing simple sine and cosine plots

This recipe will go over basics of plotting mathematical functions and several things that are related to math graphs such as writing Greek symbols in labels and on curves.

Getting ready

The most common graph we will use is the line plot command, which draws the given (x,y) coordinates on a figure plot.

How to do it...

We start with computing sine and cosine functions over the same linear interval—from Pi to Pi with 256 points in between and we plot the values for sin(x) and cos(x) over the same plot as shown here:

import matplotlib.pyplot as pl
import numpy as np

x = np.linspace(-np.pi, np.pi, 256, endpoint=True)

y = np.cos(x)
y1 = np.sin(x)

pl.plot(x,y)
pl.plot(x, y1)

pl.show()

That will give us the following graph: ...