What is tuple in python

For beginners, sometimes it is difficult to distinguish python data types, such as lists, dictionaries, tuples, etc., which are easy to confuse. Let’s talk about them below.

1. First, let’s look at the most basic differences between the three:

List is sequential and variable.

Dictrionary is unordered and variable. Dictionary is one of the built-in data types that defines a one-to-one relationship between keys and values. Each element is a key-value pair, and the entire set of elements is enclosed in curly brackets.

Tuple is a sequential, immutable list. Once a tuple is created it cannot be altered in any way.

Defining tuple is the same as defining list, except that the entire set of elements is surrounded by parentheses instead of square brackets

You are right, Tuple is an immutable list. Once a tuple is created it cannot be altered in any way.

2. The similarities between Tuple and list

Defining tuple is the same as defining list, except that the entire set of elements is surrounded by parentheses instead of square brackets.

The elements of Tuple are sorted in the defined order like list. Tuples are indexed at 0 like lists, so the first element of a non-empty tuple is always t[0].

Negative indexes start counting from the end of the tuple like list.

Like list, slices can also be used. Note that when you split a list, you get a new list; when you split a tuple, you get a new tuple.

3. Methods that Tuple does not exist

Cannot add elements to tuple. Tuple has no append or extend methods.

Cannot remove elements from tuple. Tuple has no remove or pop methods.

Cannot find elements in tuple. Tuple has no index method.

However, you can use in to see if an element exists in the tuple.

4. Advantages of using Tuple

Tuple is faster than list operation. If you define a constant set of values ​​and the only thing you want to do with it is iterate over it over and over, use a tuple instead of a list.

If you "write-protect" data that does not need to be modified, the code can be made safer. Using tuple instead of list is like having an implicit assert statement that the data is constant. If these values ​​must be changed, a tuple to list conversion needs to be performed.

5. Conversion of Tuple and List

Tuple can be converted to list and vice versa. The built-in tuple function takes a list and returns a tuple

with the same elements while the list function takes a tuple and returns a list. In effect, tuple freezes a list, and list unfreezes a tuple.

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