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Python-Cheat-Sheet

Variables & Assignments​

Creating a Variable: Simply assign a value to a variable name.

x = 10
name = "Alice"

# Multiple Assignments: Assign multiple variables at once.
a, b, c = 5, 3.2, "Hello"

Basic Operations​

Arithmetic:​

  • + (Addition)
  • - (Subtraction)
  • * (Multiplication)
  • / (Division)
  • % (Modulus)
  • ** (Power)
  • // (Floor Division)
sum = 7 + 3                 # 10
difference = 7 - 3          # 4
product = 7 * 3             # 21
quotient = 7 / 3            # 2.333...
remainder = 7 % 3           # 1
power = 7 ** 3              # 343 (7^3)
floor_quotient = 7 // 3     # 2

Comparison:​

  • == (Equal to)
  • != (Not equal to)
  • > (Greater than)
  • < (Less than)
  • >= (Greater than or equal to)
  • <= (Less than or equal to)
7 == 3  # False
7 != 3  # True
7 > 3   # True
7 < 3   # False
7 >= 3  # True
7 <= 3  # False

List Operations​

Creating a List: List are created using square brackets.

fruits = ["apple", "banana", "cherry"]

Accessing List Items​

Items in a list are indexed starting from zero. Items are accessed using [index] after the variable name. Negative numbers can be used to refer to the position relative to the end of the list.

first_fruit = fruits[0]         # "apple"
second_fruit = fruits[1]        # "banana"
third_fruit = fruits[3]         # "cherry
last_fruit = fruits[-1]         # "cherry"
second_last_fruit = fruits[-2]  # "banana"

Adding Items​

Items can be added using the append() method.

fruits.append("orange")

Removing Items​

Items can be removed using the remove() method.

fruits.remove("banana")

Logic Control Structures​

If Statement​

if age < 18:
    print("Minor")
elif age == 18:
    print("Just turned 18")
else:
    print("Adult")

For Loop​

Iterating over a sequence.

for fruit in fruits:
    print(fruit)

While Loop​

Executing as long as a condition is true.​

count = 5
while count > 0:
    print(count)
    count -= 1

Functions​

Defining a Function​

def greet(name):
    return f"Hello, {name}!"

Calling a Function​

message = greet("Alice")
print(message)

Built-in Functions​

  • print(): Display output.
  • len(): Return the length of an object.
  • int(), float(), str(): Convert to the respective type.
  • input(): Read a string from standard input.
  • range(): Generate a sequence of numbers.
print("Hello, World!")
number_of_fruits = len(fruits)
age = int(input("Enter your age: "))

This cheat sheet covers the very basics in Python programming. As you progress, you'll encounter more complex data types, advanced functions, and Python's extensive standard libraries.