Interactive Data Exploration with Matplotlib Cursor

Introduction

The matplotlib.widgets.Cursor is a useful tool for exploring the data plotted on a Matplotlib graph. It allows you to interactively display the x and y values of the data point under the cursor.

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Import Required Libraries

In this step, we import the required libraries: matplotlib.pyplot and numpy.

import matplotlib.pyplot as plt
import numpy as np

Generate Data

In this step, we generate random data points using numpy.

## Fixing random state for reproducibility
np.random.seed(19680801)

## Generate random data points
x, y = 4*(np.random.rand(2, 100) - .5)

Create a Figure and Axes

In this step, we create a figure and axes object using plt.subplots.

fig, ax = plt.subplots(figsize=(8, 6))

Plot Data Points

In this step, we plot the generated data points on the axes object.

ax.plot(x, y, 'o')
ax.set_xlim(-2, 2)
ax.set_ylim(-2, 2)

Create a Cursor

In this step, we create a cursor object using Cursor class and pass the axes object as an argument. We also specify the cursor color and line width.

cursor = Cursor(ax, useblit=True, color='red', linewidth=2)

Display the Plot

In this step, we display the plot using plt.show().

plt.show()

Summary

In this tutorial, we learned how to use the matplotlib.widgets.Cursor to interactively display the x and y values of the data point under the cursor. We generated random data points using numpy, created a figure and axes object, plotted the data points, created a cursor object and displayed the plot using plt.show().