5.5. Trigonometry

In addition to arithmetical operators, NumPy provides lots of essential functions and constants to perform trigonometrical operations:

• np.pi: π

• np.sin: Sinus

• np.cos: Cosinus

• np.tan: Tangent

• np.arcsin: Arc-sinus

• np.arccos: Arc-cosinus

• np.arctan: Arc-tangent

• np.arctan2: Arc-tangent in the full plane, contrarily to np.arctan that only returns values from -π/2 (-90°) to +π (+90°)

• np.deg2rad: Convert degrees to radians

• np.rad2deg: Convert radians to degrees

• np.abs: Absolute value

• np.sqrt: Square root

In all trigonometric functions, angles are in radians by default. You can either convert to/from degrees by multiplying or dividing by \(\pi/180\) manually, or use np.deg2rad and np.rad2deg.

import numpy as np
import matplotlib.pyplot as plt

angle = np.linspace(0, 2 * np.pi, 100)

plt.plot(angle, np.sin(angle));