Wool ()() Function in Python

This guide covers wool ()() function in python with practical context and easy-to-follow details. Use it to understand the subject and apply the information confidently.

Wool ()() Function Syntax in Python

len(chuoi)

Wool Function Parameters ()()

Wool () has 1 parameter:

• String : String (can be string, bytes, tuple, list, range, dictionary, set or frozen set) that you want to calculate the length.

Value Returned from Wool ()()

• The len function returns the number of characters of the input string. If the parameter or parameter is not passed, the program generates a TypeError exception.

Example 1: How Does the Function Len ()() Work with the Parameters of

testList = []
print(testList, 'co do dai la', len(testList))

testList = [1, 2, 3]
print(testList, 'co do dai la', len(testList))

testTuple = (1, 2, 3)
print(testTuple, 'co do dai la', len(testTuple))

testRange = range(1, 10)
print('Do dai cua', testRange, 'la', len(testRange))

Run the program, the result is returned

[] co do dai la 0
[1, 2, 3] co do dai la 3
(1, 2, 3) co do dai la 3
Do dai cua range(1, 10) la 9

Example 2: How Does the Len ()() Function Work with Parameters That Are

testString = ''
print('Do dai cua', testString, 'la', len(testString))

testString = 'Tipsmake'
print('Do dai cua', testString, 'la', len(testString))

# byte object
testByte = b'Tipsmake'
print('Do dai cua', testByte, 'la', len(testByte))

testList = [1, 2, 3]

# converting to bytes object
testByte = bytes(testList)
print('Do dai cua', testByte, 'la', len(testByte))

Running the program we get the result is:

Do dai cua la 0
Do dai cua Tipsmake la 11
Do dai cua b'Tipsmake' la 11
Do dai cua b'x01x02x03' la 3

Example 3: How Does the Len ()() Function Work with Parameters That Are

testSet = {1, 2, 3}
print(testSet, 'co do dai la', len(testSet))

# Empty Set
testSet = set()
print(testSet, 'co do dai la', len(testSet))

testDict = {1: 'mot', 2: 'hai'}
print(testDict, 'co do dai la', len(testDict))

testDict = {}
print(testDict, 'co do dai la', len(testDict))

testSet = {1, 2}

# frozenSet
frozenTestSet = frozenset(testSet)
print(frozenTestSet, 'co do dai la', len(frozenTestSet))

The result returned is:

{1, 2, 3} co do dai la 3
set() co do dai la 0
{1: 'mot', 2: 'hai'} co do dai la 2
{} co do dai la 0
frozenset({1, 2}) co do dai la 2

When executed, len () calls the __len__ method of the object, so you can also imagine the len () function as:

def len(s):
 return s.__len__()

Therefore, you can assign custom lengths to objects (if needed).

Example 4: How Does the Len ()() Function Work with Custom Objects?

class Session:
 def __init__(self, number = 0):
 self.number = number

 def __len__(self):
 return self.number


# ?? dài m?c ??nh là 0
# vi?t b?i TipsMake.com
s1 = Session()
print(len(s1))

# gán chi?u dài tùy ch?nh
s2 = Session(6)
print(len(s2))

Run the program, the returned result is:

0
6 

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