Matplotlib Basics

Introduction

Matplotlib is the foundational plotting library for Python, enabling creation of a wide variety of charts.

Basic Plot

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0, 10, 100)
y = np.sin(x)

plt.plot(x, y)
plt.xlabel("X axis")
plt.ylabel("Y axis")
plt.title("Sine Wave")
plt.show()

Multiple Plots

# Subplots
fig, axes = plt.subplots(2, 2)

axes[0, 0].plot(x, y)
axes[0, 1].plot(x, np.cos(x))
axes[1, 0].plot(x, np.tan(x))
axes[1, 1].plot(x, x**2)

plt.tight_layout()
plt.show()

Chart Types

# Line plot
plt.plot(x, y)

# Scatter plot
plt.scatter(x, y)

# Bar plot
plt.bar(x, y)

# Histogram
plt.hist(data, bins=30)

# Pie chart
plt.pie(values, labels=labels)

Practice Problems

1. Create line plot of stock prices
2. Build scatter plot with different markers
3. Compare multiple line charts
4. Add legends and annotations
5. Customize colors and styles