Introduction to Python data structure method three ———— tuples

A python tuple is similar to a list, except that the elements of a tuple cannot be modified. Tuples use parentheses, and tuples are created simply by adding elements in parentheses and separating them with commas, and you need to add a comma after the element when the tuple contains only one element.

The difference between a tuple and a list:

1, the tuple is immutable, the list is variable.

2, the tuple is more secure than the list, and the operation speed is faster.

First, create a tuple

tuple1= (1,2,3,4) tuplt2= (' A ', ' B ', ' C ', ' d ')

Second, access to tuples

A tuple's access is the same as a list, and is accessed using index values.

TUPLE1[1]2TUPLE1[-1] If the index range is exceeded, Python will report an exception. Tuple1[6]traceback (most recent): Python Shell, prompt 4, line 1indexerror:tuple index out of range

Index error: Tuple index out of range

Three, Slice

The slices of the tuple are the same as the list, including only the starting position, not the end position.

Tuple1[0:2] (1, 2)

An empty tuple is returned when the start position of the slice is outside the index range.

Tuple1[5:] ()

Iv. Methods of tuples

Because tuples are not modifiable, there are very few methods for tuples.

The number of occurrences of the 1.count statistic element, returning an integer

T.count (value), integer--return number of occurrences of value

Tuple1.count (1) 1

2.index finding the index position of an element

T.index (value, [Start, [stop]]), integer-return first index of value. Raises valueerror if the value is not present.

Tuple1.index (2) 1

V. Conversion of tuples and lists

1 tuples converted to list print tuple1 (1, 2, 3, 4) test=list (tuple1) print test[1, 2, 3, 4]2. List reload for tuple print test[1, 2, 3, 4]tuple1=tuple (test) PR int Tuple1 (1, 2, 3, 4)

Introduction to Python data structure method three ———— tuples