The name ‘StandardScaler' is not defined - Python

When working on the Python project, if you receive the error message stating, “NameError: name ‘StandardScaler’ is not defined,” it means sci-kit-learn, an open-source library for machine learning, has not been included in the array of tools in use. Let’s simplify what this means by explaining its causes and solutions.

Table of Content

• What is StandardScaler?
• Why Do You See This Error?
• How to Fix It?
• Conclusion
• FAQ’s

What is StandardScaler?

StandardScaler is a tool that rescales the data. It ensures that the set of numbers is centered around 0 with a standard deviation of 1, which allows some algorithms to work even better, mainly those that depend on the scale of the numbers, like linear regression, support vector machines, and k-nearest neighbors.

Why Do You See This Error?

This error happens when Python doesn’t know what StandardScaler is. It can be most likely because:

1. When you forget to import StandardScaler before using it, it will show this error.
2. When there’s a problem with the scikit-learn library or it’s not installed on your system, then you will see this error.
3. Sometimes people misspell the name; that is also the case when it shows this error.

How to Fix It?

Import StandardScaler

StandardScaler must be imported before you call on it. Just include this line in the initial part of your code: 

from sklearn.preprocessing import StandardScaler

Then you can create a StandardScaler object in the following way:

scaler = StandardScaler()

Install the scikit-learn library

If it is not resolved and still shows the error, it may be due to a lack of installation of the scikit-learn library. You may install sci-kit-learn using the following:
pip install scikit-learn

Check Your Environment

If you use a virtual environment or specific software such as Jupyter Notebook, install sci-kit-learn there, too. 

Conclusion

So far in this blog, we have learned what is the cause of the error “The Name ‘standardscaler‘ Is Not Defined” is and how to resolve it. Since the StandardScaler is not recognized in Python, this error might be resolved easily. Just make sure to import it correctly and install Scikit-learn. Once you do that, you can improve your machine-learning projects with the help of StandardScaler.If you are interested in learning more about StandardScaler and other tools, you can check Intellipaat’s Python course.

FAQs

1. What is StandardScaler in Python?

StandardScaler is a tool that rescales the data. It makes sure that the set of numbers is centered around 0 with a standard deviation of 1.

2. What is the use of StandardScaler?

StandardScaler improves algorithm performance for features whose scale needs adjustment by removing the mean along with unit variance scaling.

3. When should I use StandardScaler?

You should use StandardScaler, when your data gets benefits from scaling like linear regression, SVM, or k-NN.

4. What is the difference between StandardScaler and MinMaxScaler in Python?

The MinMaxScaler transforms features into the specified range of [0, 1] by subtracting minimum values while dividing by the data range.

The StandardScaler uses Standard Normal Distribution (SND). It scales features by subtracting mean values to achieve unit variance.