Python Operators¶

Operators are symbols that compare values, combine conditions, and produce True/False results.

Operators are used for:

• branching (if, elif, else)
• filtering data
• validation and decision logic

Knowing operators improves our ability to write clear analytics.

What Is an Operator?¶

An operator is a symbol that performs an operation on one or more values.

Example:

score > 5

• is the operator

• score and 5 are operands
• the result is a Boolean: True or False

Comparison Operators (Most Important)¶

Comparison operators compare two values and return True or False.

Examples:

age >= 18
score < 5.0
country == "USA"

These are the most common operators used in data analysis.

Boolean Operators (Combining Conditions)¶

Boolean operators combine multiple conditions.

Examples:

score >= 4.0 and score <= 7.5
region == "Europe" or region == "Asia"
not has_missing_values

Membership Operators (in, not in)¶

Membership operators test whether a value exists in a collection.

Examples:

"csv" in ["csv", "json", "excel"]
country not in banned_countries

This is commonly used when validating inputs or filtering data.

Identity Operators (is, is not)¶

Identity operators test whether two variables refer to the same object, not just equal values.

Examples:

value is None
result is not None

Use is primarily when checking for None.

Arithmetic Operators (Brief Review)¶

Arithmetic operators perform mathematical calculations.

Examples:

total = count \* price
average = sum(values) / len(values)
remainder = total % 2

Operator Results Feed Branching¶

Operators are most often used inside if statements.

Example:

if score >= 6.0:
   print("High score")

The condition inside if must evaluate to True or False.

Common Mistakes¶

Using only one equal sign instead of two equal signs for comparison.

• One = is used to initialize or set a variable value.
• Two == are used to test for equality.

WRONG: if x = 5:

RIGHT: if x == 5: (Use == to compare)

Comparing incompatible types

WRONG: "5" > 3 (comparing a string to an int)

RIGHT: int("5") > 3 (Convert types explicitly when needed)