What is the difference between set and list in Python
Sets can't contain duplicates while lists can
Sets are unordered while lists are ordered sequences
In order to find an element in a set, a hash lookup is used (which is why sets are unordered). This makes __contains__ (in operator) a lot more efficient for sets than lists. Elements of a list can be found by index as lists are ordered collections
Sets can only contain hashable items while lists can contain any objects
Sets are unordered while lists are ordered sequences
In order to find an element in a set, a hash lookup is used (which is why sets are unordered). This makes __contains__ (in operator) a lot more efficient for sets than lists. Elements of a list can be found by index as lists are ordered collections
Sets can only contain hashable items while lists can contain any objects
Differences between a list and an array in python
- A list is a container of objects and can hold elements of different data types
- Lists are built-in data types in python, so no import is needed to use them
- A list is flexible and can be changed after its creation.
- Some arithmetic operations are supported and they are not element-wise
- An entire list can be printed without a loop
- A list does not use memory efficiently and is typically slower than an array
- An array is a container of objects and can hold elements of the same data type only
- Arrays are not built-in data types in python, so an import is needed to use them
- Once an array is defined, its size is fixed and cannot be changed
- All arithmetic operations are supported and are element-wise
- A loop is needed to print an entire array
- An array uses memory efficiently and is typically faster than a list
|
Though lists and arrays are containers of data and can be indexed and sliced, there are many differences between them:
|
|
A list is a container of objects and can hold elements having different data types.
An array is a container of objects and can hold elements of the same data type only. |
|
Lists are built-in data types in python, so no import is needed to use them
Arrays are not built-in data types in python, so an import is needed to use them |
|
Not all arithmetic operations are supported and supported ones are not element-wise
All arithmetic operations are supported and are element-wise |
|
A list is flexible and can change after its creation. Elements can be added, deleted or modified
Once the array is defined, the space it occupies in memory, a combination of the number of its elements and the size of each element, is fixed and cannot be changed. The only thing you can do is to create a new array and replace some of its elements by the elements of the original array. |
|
An entire list can be printed without a loop
A loop is needed to print an entire array |
|
A list does not use memory efficiently and is typically slower than an array
An array uses memory efficiently and is typically faster than a list |
