11.5. Operators in Python

• Arithmetic Operators: +, -, *, /, //, %, **

Arithmetic operators are used to perform mathematical calculations in Python. The most common arithmetic operators include:

• Addition (+): Adds two operands. For example, 2 + 3 results in 5.
• Subtraction (-): Subtracts the second operand from the first. For example, 5 - 2 results in 3.
• Multiplication (*): Multiplies two operands. For instance, 4 * 5 results in 20.
• Division (/): Divides the first operand by the second. For example, 10 / 2 results in 5.0 (note that this will always return a float).
• Floor Division (//): Divides and returns the largest integer less than or equal to the result. For example, 10 // 3 results in 3.
• Modulus (%): Returns the remainder of the division. For example, 10 % 3 results in 1.
• Exponentiation (**): Raises the first operand to the power of the second. For example, 2 ** 3 results in 8 (2 raised to the power of 3).

Think of arithmetic operators as tools in a toolbox. If you have a hammer (the addition operator), a screwdriver (the subtraction operator), and other tools, each one helps you achieve a different task in building something, just like how these operators help you perform different calculations.

• Relational Operators: ==, !=, >, <, >=, <=

Relational operators are used to compare two values. The result of a relational operation is either true or false. The commonly used relational operators include:

• Equal to (==): Checks if two values are equal. For example, 5 == 5 returns True.
• Not equal to (!=): Checks if two values are not equal. For example, 5 != 4 returns True.
• Greater than (>), Less than (<): Compares two values. For instance, 5 > 3 returns True, while 2 < 1 returns False.
• Greater than or equal to (>=): Checks if the left value is greater than or equal to the right value. For example, 5 >= 5 returns True.
• Less than or equal to (<=): Checks if the left value is less than or equal to the right value. For example, 6 <= 7 returns True.

Imagine you have a race between two participants. If one person runs faster (greater than), they win (True), if they run slower (less than), they lose (False). Relational operators help you determine who wins based on their speeds.

• Logical Operators: and, or, not

Logical operators are used to combine conditional statements. Their outputs are based on the truthiness of the statements they combine. The basic logical operators include:

• And: A and B returns True if both A and B are true.
• Or: A or B returns True if at least one of A or B is true.
• Not: not A returns True if A is false and False if A is true. For example, not True returns False.

Think of an 'and' operator like a team sport. For your team to win, both players must score points (both conditions must be true). An 'or' operator is like an or-mention, where only one needs to score (at least one condition must be true). The 'not' operator is like a referee whose job is to rule against a player if they break the rules.

• Assignment Operators: =, +=, -=, etc.

Assignment operators are used to assign values to variables. The fundamental assignment operator is:

• Assignment (=): Assigns the value of the right operand to the left operand. For example, x = 10 assigns the value 10 to x.
• Compound assignment operators combine an arithmetic operation with assignment. For instance, x += 5 is equivalent to x = x + 5, which adds 5 to x and reassigns it.

Think of a variable as a box you can put things in. The assignment operator (=) is like sealing the box with a specific item inside it (assigning a value). When you use +=, it's like adding more items into the already sealed box instead of replacing it.

Example: x = 10 y = 5 print(x + y) # 15

This simple example demonstrates how arithmetic operations work in Python. In the code snippet:

• x is assigned the value 10 and y is assigned the value 5.
• The expression x + y uses the addition operator to add these two numbers together.
• The print function displays the result (which is 15) on the screen.

Suppose you have 10 apples in one basket (x) and 5 more in another basket (y). If you put them all together and count, you get 15 apples. This is what happens when you use an addition operator in your code.

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