python--Meta-Group

tuple tuples

Why do I need tuples ?

For example : Print the user's name

Userinfo1 = "Fentiao 4 Male"

Userinfo[0:7]

Conclusion : The method of extracting name / age / Gender in the string is inconvenient , the birth tuple .

First, definition of tuples

( you can think of tuples as a container, and any data type can be placed inside this container. )

- Create tuples by assigning values;

- Create tuples from factory method

?- define an empty tuple

tuple = ()

?- A tuple that defines a single value , Be sure to add a comma after this element

Tuple = (A,)

?- General tuples

tuple = (b, 8, ' male ')

Second, Tuple Properties

? You cannot change the value of a tuple arbitrarily ;

? assign a value to a tuple individually , extended to multiple variables can also be divided by the tuple way

Do not assign a value

Third, operation of tuples

tuples also belong to the sequence, which can be performed as follows :

index, slice, repeat, connect, and view length

Delete

Four, Tuple's method

? T.count (value)-->int

returns the number of occurrences of value in a tuple ;

? T.index (value)

returns the offset of value in the tuple ( that is, the index value )

Five, the cycle of the tuple

The loop of the string:

Can iterate over objects

Demo: Port selector prototype

Enumeration method

Zip

python--Meta-Group