Hướng dẫn check if number python
IntroductionIn this article, we'll be going through a few examples of how to check if a variable is a number in Python. Python is dynamically typed. There is no need to declare a variable type, while instantiating it - the interpreter infers the type at runtime:
Additionally, a variable can be reassigned to a new type at any given time:
This approach, while having advantages, also introduces us to a few issues. Namely, when we
receive a variable, we typically don't know of which type it is. If we're expecting a Number, but receive Using the type() FunctionThe
This results in:
Thus, a way to check for the type is:
Here, we check if the variable type,
entered by the user is an If we just said
This, regardless of the input, returns:
This is because Python checks for
truth values of the statements. Variables in Python can be evaluated as Hence when we write numbers.NumberA good way to check if a variable is a number is the
This will result in:
Check out our hands-on, practical guide to learning Git, with best-practices, industry-accepted standards, and included cheat sheet. Stop Googling Git commands and actually learn it! Note: This approach can behave unexpectedly with numeric types outside of core Python. Certain frameworks might have non- Using a try-except blockAnother method to check if a variable is a number is using a try-except block. In the try block, we cast the given variable to an
This works for both If you specifically only want to check if a variable is one of these, you should use the ConclusionPython is a dynamically typed language, which means that we might receive a data type different than the one we're expecting. In cases where we'd want to enforce data types, it's worth checking if a variable is of the desired type. In this article, we've covered three ways to check if a variable is a Number in Python. |