Operators in Python

Master arithmetic, comparison, and assignment operators in Python with practical examples

Introduction to Operators

Operators are special symbols in Python that perform operations on values and variables. Python supports various types of operators including arithmetic, comparison, and assignment operators.

Arithmetic Operators

Arithmetic operators perform mathematical calculations on numeric values.

Basic Arithmetic Operations

numeroA = 4
numeroB = 2

# Addition (+)
print(numeroA + numeroB)  # 6

# Subtraction (-)
print(numeroA - numeroB)  # 2

# Multiplication (*)
print(numeroA * numeroB)  # 8

# Division (/)
print(numeroA / numeroB)  # 2.0

Division (/) always returns a float, even when dividing evenly. Use // for integer division.

Advanced Arithmetic Operations

# Modulo - returns remainder of division (%)
print(13 % 5)  # 3

# Exponentiation - raises to power (**)
print(2 ** 8)  # 256

Arithmetic Operators Summary

Operator	Name	Example	Result
+	Addition	4 + 2	6
-	Subtraction	4 - 2	2
*	Multiplication	4 * 2	8
/	Division	4 / 2	2.0
%	Modulo	13 % 5	3
**	Exponentiation	2 ** 8	256
//	Floor Division	7 // 2	3

Assignment Operators

Assignment operators are used to assign and modify variable values.

Increment Operations

# Increment by one
numeroTemp1 = 2
numeroTemp1 += 1
print(numeroTemp1)  # 3

# Increment by multiple units
numeroTemp3 = 3
numeroTemp3 += 5
print(numeroTemp3)  # 8

Decrement Operations

# Decrement by one
numeroTemp2 = 5
numeroTemp2 -= 1
print(numeroTemp2)  # 4

# Decrement by multiple units
numeroTemp4 = 13
numeroTemp4 -= 4
print(numeroTemp4)  # 9

Python doesn’t have ++ or -- operators like other languages. Use += 1 and -= 1 instead.

Assignment Operators Summary

Operator	Example	Equivalent To
=	x = 5	x = 5
+=	x += 3	x = x + 3
-=	x -= 3	x = x - 3
*=	x *= 3	x = x * 3
/=	x /= 3	x = x / 3
%=	x %= 3	x = x % 3
**=	x **= 3	x = x ** 3

Comparison Operators

Comparison operators compare two values and return a boolean result (True or False).

Equality Comparison

NUMERO1 = 20
NUMERO2 = "20"
NUMERO3 = 30

# Equal to (==)
print(10 == 10)  # True
print(10 == 14)  # False
print(2 == "2")   # False (different types)
print(2 == int("2"))  # True
print(NUMERO1 == int(NUMERO2))  # True
print(NUMERO1 == NUMERO3)  # False

The equality operator (==) checks both value and type. 2 == "2" is False because one is an integer and the other is a string.

Inequality Comparison

# Not equal to (!=)
print(10 != 10)  # False
print(10 != 14)  # True
print(2 != "2")  # True
print(2 != int("2"))  # False

PASSWORD = "Abc123"
PASSWORD_CONFIRMATION = "ABC123"
print(PASSWORD != PASSWORD_CONFIRMATION)  # True

Greater Than and Less Than

NUMERO1 = 20
NUMERO3 = 30

# Greater than (>)
print(f"¿{NUMERO1} es mayor que {NUMERO3}? => {NUMERO1 > NUMERO3}")  # False

# Less than (<)
print(f"¿{NUMERO1} es menor que {NUMERO3}? => {NUMERO1 < NUMERO3}")  # True

Greater/Less Than or Equal To

# Greater than or equal to (>=)
print(f"¿{NUMERO1} es mayor o igual que {NUMERO2}? => {NUMERO1 >= int(NUMERO2)}")  # True

# Less than or equal to (<=)
print(f"¿{NUMERO1} es menor o igual que {NUMERO3}? => {NUMERO1 <= NUMERO3}")  # True

Comparison Operators Summary

Operator	Name	Example	Result
==	Equal to	10 == 10	True
!=	Not equal to	10 != 14	True
>	Greater than	20 > 30	False
<	Less than	20 < 30	True
>=	Greater than or equal	20 >= 20	True
<=	Less than or equal	20 <= 30	True

Practical Examples

Example 1: Calculator Operations

numeroA = 4
numeroB = 2

print(f"Suma: {numeroA + numeroB}")
print(f"Resta: {numeroA - numeroB}")
print(f"Multiplicación: {numeroA * numeroB}")
print(f"División: {numeroA / numeroB}")
print(f"Módulo: {numeroA % numeroB}")
print(f"Potencia: {numeroA ** numeroB}")

Example 2: Password Validation

PASSWORD = "Abc123"
PASSWORD_CONFIRMATION = "ABC123"

if PASSWORD != PASSWORD_CONFIRMATION:
    print("Las contraseñas no coinciden")
else:
    print("Las contraseñas coinciden")

Example 3: Counter Updates

# Initialize counter
counter = 0

# Increment counter
counter += 1
print(f"Counter after increment: {counter}")  # 1

# Add multiple units
counter += 5
print(f"Counter after adding 5: {counter}")  # 6

# Decrement counter
counter -= 2
print(f"Counter after decrement: {counter}")  # 4

Type Checking with isinstance()

You can check variable types using comparison with isinstance():

estatura = 4.0

# Check if variable is float and meets condition
print(estatura >= 1.71 and type(estatura) == float)  # True
print(estatura >= 1.71 and isinstance(estatura, int))  # False

isinstance() is the preferred way to check types in Python. It’s more flexible than type() as it considers inheritance.

Key Takeaways

• Arithmetic operators perform mathematical calculations
• Assignment operators modify variable values in place
• Comparison operators return boolean values (True or False)
• Python is type-sensitive in comparisons: 2 == "2" is False
• Use += and -= for incrementing/decrementing (Python has no ++ or --)
• Division (/) always returns a float, even for whole number results