What Python Error Is Y X 3 Z

Python Programming

Hey there! Today, I want to talk to you about a common Python error that you might come across in your programming journey. The error is “NameError: name ‘y’ is not defined.”

Now, let’s dive deep into the details of this error and understand what it means.

When you see the error message “NameError: name ‘y’ is not defined,” it means that Python has encountered a variable or a name that it doesn’t recognize. In this case, it is the variable ‘y’ that is causing the error.

Python is a dynamically-typed language, which means that you can create variables on the fly without explicitly declaring their type. However, before you can use a variable, you need to assign a value to it.

In the case of “y x 3 z,” Python treats ‘y,’ ‘x,’ and ‘z’ as variable names. But since we haven’t assigned any values to these variables, Python throws a NameError.

Let’s take a closer look at the error message:

NameError: name 'y' is not defined

The error message consists of two parts:

  1. “NameError” – Indicates that there is an issue with a name or variable.
  2. “name ‘y’ is not defined” – Tells us specifically that the variable ‘y’ has not been defined.

So, how do we fix this error? We simply need to define the variable ‘y’ and assign a value to it before using it in any calculations. For example:

y = 5
result = y * 3

Now, when we run the code, Python will recognize the variable ‘y’ and perform the multiplication correctly.

It’s important to remember that variable names in Python are case-sensitive. So, ‘y’ and ‘Y’ will be treated as different variables.

Now that we have a better understanding of the “NameError: name ‘y’ is not defined” error, let’s summarize what we’ve learned.


In this article, we explored the meaning and causes of the Python error “NameError: name ‘y’ is not defined.” We learned that this error occurs when Python encounters a variable or name that it doesn’t recognize. To fix the error, we need to make sure to define and assign a value to the variable before using it in our code.

Remember, errors like these are a normal part of the learning process in programming. Embrace them as opportunities to grow and improve your coding skills.

Happy coding!