python - Omit joining lines in matplotlib plot e.g. y = tan(x)

Question

I have the graph y = tan(x) and I want to remove the vertical lines (see below).

Here is my code:

import numpy as np
import matplotlib.pyplot as plt

# Choose evenly spaced x intervals
x = np.arange(-2*np.pi, 2*np.pi, 0.1)

# plot y = tan(x)
plt.plot(x, np.tan(x))

# Set the range of the axes
plt.axis([-2*np.pi, 2*np.pi, -2, 2])

# Include a title
plt.title('y = tan(x)')

# Optional grid-lines
plt.grid()

# Show the graph
plt.show()

Here is the graph (including unwanted vertical lines):

Can I remove the vertical lines without setting appropriate gaps into the x intervals?

Answer 1

You can check the difference between successive data points using diff and then identify where the difference is negative and replace these values with NaN to create a visual break in the plotted line

# Compute the tangent for each point
y = np.tan(x)

# Insert a NaN where the difference between successive points is negative
y[:-1][np.diff(y) < 0] = np.nan

# Plot the resulting discontinuous line
plt.plot(x, y)