ModuleNotFoundError: No module named ‘scipy’

In Python, ModuleNotFoundError: No module named ‘scipy’ error occurs if we try to import the ‘scipy‘ module without installing the package or if you have not installed it in the correct environment.

In this tutorial, let’s look at installing the scipy module correctly in different operating systems and solve ModuleNotFoundError: No module named ‘scipy’ error.  

What is ModuleNotFoundError: No module named ‘scipy’?

There are various reasons why we get the ModuleNotFoundError: No module named ‘scipy’ error

• Trying to use the module without installing the scipy package.
• If the IDE is set to the incorrect version of the Python/Python interpreter.
• You are using the virtual environment and the scipy module is not installed inside a virtual environment
• Installing the scipy package in a different version of Python than the one which is used currently.
• Declaring a variable name as the module name(scipy)

If you are getting an error installing pip, checkout pip: command not found to resolve the issue.

How to fix ModuleNotFoundError: No module named ‘scipy’?

scipy is not a built-in module (it doesn’t come with the default python installation) in Python; you need to install it explicitly using the pip installer and then use it.  

SciPy (pronounced “Sigh Pie”) is open-source software for mathematics, science, and engineering. The SciPy library depends on NumPy, which provides convenient and fast N-dimensional array manipulation. The SciPy library is built to work with NumPy arrays, and provides many user-friendly and efficient numerical routines such as routines for numerical integration and optimization.

We can fix the error by installing the ‘scipy‘ module by running the pip install scipy command in your terminal/shell.

We can verify if the package is installed correctly by running the following command in the terminal/shell.

This will provide the details of the package installed, including the version number, license, and the path it is installed. If the module is not installed, you will get a warning message in the terminal stating WARNING: Package(s) not found: scipy.

pip show scipy

Output

Name: scipy
Version: 1.9.0
Summary: SciPy: Scientific Library for Python
Home-page: https://www.scipy.org
Author:
Author-email:
License: BSD
Location: c:\personal\ijs\python_samples\venv\lib\site-packages
Requires: numpy

Solution 1 – Installing and using the scipy module in a proper way

Based on the Python version and the operating system you are running, run the relevant command to install the scipy module.

# If you are using Python 2 (Windows)
pip install scipy

# if you are using Python 3 (Windows)
pip3 install scipy

# If the pip is not set as environment varibale PATH
python -m pip install scipy

# If you are using Python 2 (Linux)
sudo pip install scipy

# if you are using Python 3 (Linux)
sudo pip3 install scipy

# In case if you have to easy_install
sudo easy_install -U scipy

# On Centos
yum install scipy

# On Ubuntu
sudo apt-get install scipy

# If you are installing it in Anaconda 
conda install -c anaconda scipy

Once you have installed the scipy module, we can now import it inside our code and use it as shown below.

from scipy import constants

print(constants.yotta)
print(constants.zetta)
print(constants.exa)
print(constants.peta)
print(constants.tera)
print(constants.giga)
print(constants.mega)
print(constants.kilo)

Output

1e+24
1e+21
1e+18
1000000000000000.0
1000000000000.0
1000000000.0
1000000.0
1000.0

Solution 2 – Verify if the IDE is set to use the correct Python version

If you are still getting the same error even after installing the package, you can verify if the IDE you are using is configured with the correct version of the Python interpreter.

For Eg:- In the case of Visual Studio Code, we can set the Python version by pressing CTRL + Shift + Por (⌘ + Shift + P on Mac) to open the command palette.

Once the command palette opens, select the Python interpreter and select the correct version of Python and also the virtual environment(if configured).

Solution 3 – Installing scipy inside the virtual environment

Many different IDEs like Jupyter Notebook, Spyder, Anaconda, or PyCharm often install their own virtual environment of Python to keep things clean and separated from your global Python.

If you are using VS Code, then you can also create a virtual environment, as shown below.

In the case of virtual environments, you need to ensure that the scipy module needs to be installed inside the virtual environment and not globally.

Step 1: Create a Virtual Environment. If you have already created a virtual environment, then proceed to step 2.

Step 2: Activate the Virtual Environment

Step 3: Install the required module using the pip install command

# Create a virtual Environment
py -3 -m venv venv

# Activate the virtual environment (windows command)
venv\Scripts\activate.bat

# Activate the virtual environment (windows powershell)
venv\Scripts\Activate.ps1

# Activate the virtual environment (Linux)
source venv/bin/activate

# Install scipy inside the virtual environment
pip install scipy

Solution 4 – Ensure that a module name is not declared name a variable name.

Last but not least, you may need to cross-check and ensure that you haven’t declared a variable with the same name as the module name.

You should check if you haven’t named any files as scipy.py as it may shadow the original scipy module.

If the issue is still not solved, you can try removing the package and installing it once again, restart the IDE, and check the paths to ensure that packages are installed in the correct environment path and Python version.

Conclusion

The ModuleNotFoundError: No module named ‘scipy’ error occurs when we try to import the ‘scipy‘ module without installing the package or if you have not installed it in the correct environment.

We can resolve the issue by installing the scipy module by running the pip install scipy command. Also, ensure that the module is installed in the proper environment in case you use any virtual environments, and the Python version is appropriately set in the IDE that you are running the code.