How to overcome TypeError: unhashable type: 'list' [duplicate] Ask Question Asked 11 years, 1 month ago Modified 19 days ago Viewed 937k times 172 This question already has answers here : How slicing in Python works (38 answers) Why can't I use a list as a dict key in python? Exactly what can and cannot be used, and why? (11 answers) The error-"unhahasble type: list" In this section, we will look at the reason due to which this error occurs. We will take into account everything discussed so far. Let us see this through an example: 1 2 numb ={ 1:'one', [2,10]:'two and ten',11:'eleven'} print(numb) Output: TypeError: unhashable type: 'list'
Python TypeError unhashable type 'list' YouTube
The Python TypeError: unhashable type: 'list' usually means that a list is being used as a hash argument. This error occurs when trying to hash a list, which is an unhashable object. For example, using a list as a key in a Python dictionary will cause this error since dictionaries only accept hashable data types as a key. If you specify a list as a key in a dictionary, you'll encounter a "TypeError: unhashable type: 'list'" error. In this guide, we talk about what this error means and why you see it in your code. We'll walk through an example of this error to show you how to solve it. Find your bootcamp match Select Your Interest Your experience Time to start In Python, a TypeError is raised when an operation or function is applied to an object of an inappropriate type. One such error is the "TypeError: unhashable type: 'list'" error. This error occurs when we try to use a list (which is an unhashable type object) in a place that requires a hashable type. The main reason behind this problem was using an unhashable type inside the dictionary. To avoid this type of situation you may think carefully about which are hashable and which are not. Finally, by following this article you may fix the TypeError: unhashable type: 'list' in python. This guide is part of the "Common Python Errors.
Python TypeError Unhashable Type List Delft Stack
The error unhashable type: 'dict' occurs because we are trying to use a dictionary as key of a dictionary item. By definition a dictionary key needs to be hashable. What does it mean? When we add a new key / value pair to a dictionary, the Python interpreter generates a hash of the key. The hash () function is an encryption technique that encrypts the immutable object and assigns a unique value to it, known as the object's hash value. No matter the data's size, it provides the same size of unique value. Code: string_val = "String Value" tuple_val = (1, 2, 3, 4, 5) msg = """Hey there! Solution #1: Cast List to Tuple Summary TypeError: unhashable type: 'list' What Does TypeError Mean? TypeError occurs whenever you try to perform an illegal operation for a specific data type object. In the example, the illegal operation is hashing, and the data type is List. What Does Unhashable Mean? The easiest way to fix this error is to use a hashable tuple instead of a non-hashable list as a dictionary key or set element. We'll show how this is done in the remaining article. The last method is a unique way to still use lists in sets or dictionary keys that you likely won't find anywhere else, so keep reading and learn something new!
Python Typeerror Unhashable Type List Delft Stack Riset
1 Probably this can be helpful: stackoverflow.com/questions/46958331/… - Georgy Apr 25, 2018 at 10:46 Did an answer below help? Feel free to accept an answer (green tick on left), or ask for clarification. - jpp May 8, 2018 at 11:19 Add a comment 5 Answers Sorted by: 4 How to solve the typeerror unhashable type 'list' error? September 29, 2023 by Gili Fix TypeError: unhashable type: 'list' in Python Python structures such as Dictionary or a pandas DataFrame or Series objects, require that each object instance is uniquely identified .
TypeError: unhashable type: 'list' error occurs mainly when we use any list as a hash object. As you already know list is a mutable Python object. For hashing an object it must be immutable like tuple etc. Hence converting every mutable object into immutable is the fix for the error TypeError: unhashable type: 'list'. Now there is a problem to know which object is hashable and which object is not. The objects in python which are immutable and have a hash value are called hashable and which are mutable and don't have a hash value are called unhashable.
How to Fix TypeError unhashable type 'list' Data Science Parichay
6 Answers Sorted by: 38 You are creating a set via the set (.) call, and set needs hashable items. You can't have set of lists. Because lists aren't hashable. [ [ (a,b) for a in range (3)] for b in range (3)] is a list. Solution to TypeError: unhashable type: 'list'. Solution 1 - By Converting list into a tuple. Solution 2 - By Adding list as a value in a dictionary. TypeError: unhashable type: 'list' usually occurs when you use the list as a hash argument. In simple terms, if you use a list as a key in the dictionary, you will encounter a.
