A common error you may encounter when using Python is modulenotfounderror: no module named ‘plotly’.

This error occurs when the Python interpreter cannot detect the Plotly library in your current environment.

You can install Plotly in Python 3 with python3 -m pip install plotly.

This tutorial goes through the exact steps to troubleshoot this error for the Windows, Mac and Linux operating systems.


ModuleNotFoundError: no module named ‘plotly’

What is Plotly?

Plotly is an open-source graphing library for creating interactive charts and maps for Python, R, Julia, Javascript, ggplot2, F#, MATLAB, and Dash. It is used widely by data scientists, engineers, and researchers for data storytelling through visualization.

The simplest way to install Plotly for Python is to use the package manager for Python called pip. The following installation instructions are for the major Python version 3.

Always Use a Virtual Environment to Install Packages

It is always best to install new libraries within a virtual environment. You should not install anything into your global Python interpreter when you develop locally. You may introduce incompatibilities between packages, or you may break your system if you install an incompatible version of a library that your operating system needs. Using a virtual environment helps compartmentalize your projects and their dependencies. Each project will have its environment with everything the code needs to run. Most ImportErrors and ModuleNotFoundErrors occur due to installing a library for one interpreter and trying to use the library with another interpreter. Using a virtual environment avoids this. In Python, you can use virtual environments and conda environments. We will go through how to install Plotly with both.

How to Install Plotly on Windows Operating System

First, you need to download and install Python on your PC. Ensure you select the install launcher for all users and Add Python to PATH checkboxes. The latter ensures the interpreter is in the execution path. Pip is automatically on Windows for Python versions 2.7.9+ and 3.4+.

You can check your Python version with the following command:

python3 --version

You can install pip on Windows by downloading the installation package, opening the command line and launching the installer. You can install pip via the CMD prompt by running the following command.

python get-pip.py

You may need to run the command prompt as administrator. Check whether the installation has been successful by typing.

pip --version

Plotly installation on Windows Using pip

To install Plotly, first create the virtual environment. The environment can be any name, in this we choose “env”:

virtualenv env

You can activate the environment by typing the command:

env\Scripts\activate

You will see “env” in parenthesis next to the command line prompt. You can install Plotly within the environment by running the following command from the command prompt.

python3 -m pip install plotly

We use python -m pip to execute pip using the Python interpreter we specify as Python. Doing this helps avoid ImportError when we try to use a package installed with one version of Python interpreter with a different version. You can use the command which python to determine which Python interpreter you are using.

How to Install Plotly on Mac Operating System using pip

Open a terminal by pressing command (⌘) + Space Bar to open the Spotlight search. Type in terminal and press enter. To get pip, first ensure you have installed Python3:

python3 --version
Python 3.8.8

Download pip by running the following curl command:

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py

The curl command allows you to specify a direct download link. Using the -o option sets the name of the downloaded file.

Install pip by running:

python3 get-pip.py

To install Plotly, first create the virtual environment:

python3 -m venv env

Then activate the environment using:

source env/bin/activate 

You will see “env” in parenthesis next to the command line prompt. You can install Plotly within the environment by running the following command from the command prompt.

python3 -m pip install plotly

How to Install Plotly on Linux Operating Systems

All major Linux distributions have Python installed by default. However, you will need to install pip. You can install pip from the terminal, but the installation instructions depend on the Linux distribution you are using. You will need root privileges to install pip. Open a terminal and use the commands relevant to your Linux distribution to install pip.

Installing pip for Ubuntu, Debian, and Linux Mint

sudo apt install python-pip3

Installing pip for CentOS 8 (and newer), Fedora, and Red Hat

sudo dnf install python-pip3

Installing pip for CentOS 6 and 7, and older versions of Red Hat

sudo yum install epel-release

sudo yum install python-pip3

Installing pip for Arch Linux and Manjaro

sudo pacman -S python-pip

Installing pip for OpenSUSE

sudo zypper python3-pip

Plotly installation on Linux with Pip

To install Plotly, first create the virtual environment:

python3 -m venv env

Then activate the environment using:

source env/bin/activate 

You will see “env” in parenthesis next to the command line prompt. You can install Plotly within the environment by running the following command from the command prompt.

Once you have activated your virtual environment, you can install Plotly using:

python3 -m pip install plotly

Installing Plotly Using Anaconda

First, to create a conda environment to install plotly.

conda create -n project python=3.6 

Then activate the project container. You will see “project” in parentheses next to the command line prompt.

source activate project

Now you’re ready to install Plotly using conda.

Anaconda is a distribution of Python and R for scientific computing and data science. You can install Anaconda by going to the installation instructions. Once you have installed Anaconda and created your conda environment, you can install Plotly using the following command:

conda install -c plotly plotly

Check Plotly Version

Once you have successfully installed Plotly, you can check its version. If you used pip to install Plotly, you can use pip show from your terminal.

python3 -m pip show plotly
Name: plotly
Version: 5.6.0
Summary: An open-source, interactive data visualization library for Python

Second, within your python program, you can import Plotly and then reference the __version__ attribute:

import plotly
print(plotly.__version__)
5.6.0

If you used conda to install Plotly, you could check the version using the following command:

conda list -f plotly
# Name                    Version                   Build  Channel
plotly                    5.6.0                      py_0    plotly

Summary

Congratulations on reading to the end of this tutorial. The modulenotfounderror occurs if you misspell the module name, incorrectly point to the module path or do not have the module installed in your Python environment. If you do not have the module installed in your Python environment, you can use pip to install the package. However, you must ensure you have pip installed on your system. You can also install Anaconda on your system and use the conda install command to install Plotly.

Go to the online courses page on Python to learn more about Python for data science and machine learning.

For further reading on missing modules in Python, go to the article: How to Solve Python ModuleNotFoundError: no module named ‘urllib2’.

Have fun and happy researching!