Matplotlib Python Plotting Library | Jupyter Notebook Tutorial

Introduction

Matplotlib is a plotting library for the Python programming language and its numerical mathematics extension NumPy. In this tutorial, we will learn how to create a simple legend with Matplotlib.

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Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL matplotlib(("`Matplotlib`")) -.-> matplotlib/BasicConceptsGroup(["`Basic Concepts`"]) matplotlib(("`Matplotlib`")) -.-> matplotlib/PlottingDataGroup(["`Plotting Data`"]) matplotlib(("`Matplotlib`")) -.-> matplotlib/PlotCustomizationGroup(["`Plot Customization`"]) python(("`Python`")) -.-> python/DataStructuresGroup(["`Data Structures`"]) python(("`Python`")) -.-> python/ModulesandPackagesGroup(["`Modules and Packages`"]) python(("`Python`")) -.-> python/DataScienceandMachineLearningGroup(["`Data Science and Machine Learning`"]) matplotlib/BasicConceptsGroup -.-> matplotlib/importing_matplotlib("`Importing Matplotlib`") matplotlib/BasicConceptsGroup -.-> matplotlib/figures_axes("`Understanding Figures and Axes`") matplotlib/PlottingDataGroup -.-> matplotlib/line_plots("`Line Plots`") matplotlib/PlotCustomizationGroup -.-> matplotlib/line_styles_colors("`Customizing Line Styles and Colors`") matplotlib/PlotCustomizationGroup -.-> matplotlib/legend_config("`Legend Configuration`") python/DataStructuresGroup -.-> python/lists("`Lists`") python/DataStructuresGroup -.-> python/tuples("`Tuples`") python/ModulesandPackagesGroup -.-> python/importing_modules("`Importing Modules`") python/DataScienceandMachineLearningGroup -.-> python/data_visualization("`Data Visualization`") subgraph Lab Skills matplotlib/importing_matplotlib -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} matplotlib/figures_axes -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} matplotlib/line_plots -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} matplotlib/line_styles_colors -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} matplotlib/legend_config -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} python/lists -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} python/tuples -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} python/importing_modules -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} python/data_visualization -.-> lab-48942{{"`Matplotlib Legend Creation Tutorial`"}} end

Import Matplotlib

To use Matplotlib, we need to import it first.

import matplotlib.pyplot as plt

Create a Figure and Axes

We need to create a figure and axes to plot our data.

fig, ax = plt.subplots()

Plot the Data

We can plot our data using the plot() function.

line1, = ax.plot([1, 2, 3], label="Line 1", linestyle='--')
line2, = ax.plot([3, 2, 1], label="Line 2", linewidth=4)

Create the First Legend

We can create a legend for the first line using the legend() function.

first_legend = ax.legend(handles=[line1], loc='upper right')

Add the First Legend

We need to add the first legend to the plot using the add_artist() function.

ax.add_artist(first_legend)

Create the Second Legend

We can create another legend for the second line using the legend() function.

ax.legend(handles=[line2], loc='lower right')

Show the Plot

We can show the plot using the show() function.

plt.show()

Summary

In this tutorial, we learned how to create a simple legend with Matplotlib. We imported Matplotlib, created a figure and axes, plotted the data, and created and added two legends to the plot. Finally, we showed the plot using the show() function.

Matplotlib Legend Creation Tutorial