Python Must-Know Built-in Functions

Learning Python Day 4

Python Must-Know Built-in Functions

There are several built-in functions in Python that may be used to carry out a variety of tasks. No of your level of expertise as a developer, it is imperative that you understand these fundamental built-in functionalities.

You may easily do basic tasks with their help, including printing output, managing user input, modifying data, calculating values, iterating over sequences, and more.

print()

name = "John"
print("Hello, " + name + "!")  # Output: Hello, John!

The print() function is used to display output to the console.

input()

age = input("Enter your age: ")
print("You are " + age + " years old.")  # Output: You are 25 years old.

The input() function reads user input from the console.

len()

numbers = [1, 2, 3, 4, 5]
length = len(numbers)
print("The length of the list is:", length)  # Output: The length of the list is: 5

The len() function returns the number of items in an object. In this example, it calculates the length of the numbers list and prints the result.

type()

value = 10
data_type = type(value)
print("The type of the value is:", data_type)  # Output: The type of the value is: <class 'int'>

The type() function returns the type of an object. In this example, it returns the type of the value variable and prints the result.

int(), float(), str()

number = "10"
integer = int(number)
floating = float(number)
text = str(integer)
print(number, integer, floating, text)  # Output: 10 10 10.0 10

These functions are used for type conversion. In this example, the int() function converts the string "10" to an integer.

range()

for i in range(5):
    print(i)  # Output: 0 1 2 3 4

The range() function generates a sequence of numbers In this example, it generates numbers from 0 to 4, and the loop prints each number.

max(), min()

numbers = [5, 2, 8, 1, 9]
maximum = max(numbers)
minimum = min(numbers)
print("Maximum number:", maximum)  # Output: Maximum number: 9
print("Minimum number:", minimum)  # Output: Minimum number: 1

These functions are used to find the maximum and minimum values froma sequence or multiple arguments.

sum()

numbers = [1, 2, 3, 4, 5]
total = sum(numbers)
print("Sum of numbers:", total)  # Output: Sum of numbers: 15

The sum() function calculates the sum of a sequence of numbers.

abs()

number = -10
absolute_value = abs(number)
print("Absolute value:", absolute_value)  # Output: Absolute value: 10

The abs() function returns the absolute value of a number.

round()

pi = 3.14159
rounded_number = round(pi, 2)
print("Rounded number:", rounded_number) # Output: Rounded number: 3.14

The round() funciton rounds a number to a specified precision.

sorted()

numbers = [3, 1, 4, 2, 5]
sorted_list = sorted(numbers)
print("Sorted list:", sorted_list)  # Output: Sorted list: [1, 2, 3, 4, 5]

The sorted() function returns a new list with the items from an iterable sorted in ascending order.

enumerate()

fruits = ["apple", "banana", "cherry"]
for index, fruit in enumerate(fruits):
    print(index, fruit)
# Output:
# 0 apple
# 1 banana
# 2 cherry

The enumerate() function returns an iterator that pairs elements with their index.

zip()

numbers = [1, 2, 3]
letters = ['a', 'b', 'c']
for num, letter in zip(numbers, letters):
    print(num, letter)
# Output:
# 1 a
# 2 b
# 3 c

The zip() function takes multiple iterables and returns an iterator of tuples, pairing corresponding elements.

any(), all()

numbers = [0, 1, 2, 3]
any_true = any(numbers)
all_true = all(numbers)
print("Any true:", any_true)  # Output: Any true: True
print("All true:", all_true)  # Output: All true: False

The any() function returns True if any element in an iterable evaluates to True, and the all() function returns True if all elements evaluate to True.

help()

help(print)

The help() function displays information about an object, including its docstring. In this example, it provides help and documentation for the print() function.