Python Reference

Created by Brandon Concepcion

Table of Contents

1. Python Reference
   1. Data Types
   2. Arithmetic Operators
   3. Variables and Expressions

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Data Types

Data Type	Description	Examples
int	Represents integers: whole numbers that are positive or negative.	42, -100, 0
float	Represents decimal numbers (floating-point).	3.14, -1.23, 0.0
str	Represents text (strings of characters).	"Hello", 'Data'
bool	Represents boolean values (True or False).	True, False

Arithmetic Operators

Numeric Expression	Description	Examples
Addition (+)	Adds two numbers together.	2 + 3 would return 5 x + 10 adds 10 to the value of x
Subtraction (-)	Subtracts the second number from the first.	5 - 2 would return 3 x - 4 subtracts 4 from x
Multiplication (*)	Multiplies two numbers.	3 * 4 would return 12 x * 2 multiplies x by 2
Division (/)	Divides the first number by the second, returns a floating-point result.	10 / 2 would return 5.0 x / 4 divides x by 4
Floor Division (//)	Divides the first number by the second, rounds down to the nearest integer.	10 // 3 would return 3 x // 2 divides x and rounds down
Modulus (%)	Returns the remainder of dividing the first number by the second.	10 % 3 would return 1 x % 2 checks if x is even or odd (remainder)
Exponentiation (**)	Raises the first number to the power of the second number.	2 ** 3 would return 8 x ** 2 squares x
Unary Negation (-)	Returns the negative of the number.	-x returns the negative of x -10 would return -10

Variables and Expressions

Concept	Description	Examples
Expression	Any combination of values, variables, operators, and function calls that evaluates to a value.	2 + 3, x * 10, len('hello')
Variable	A name that refers to a value or an expression result. Can be reassigned to different values.	x = 10 name = "Sid"
Assignment	The process of assigning a value to a variable using the = operator.	age = 25 assigns the value of 25 to the variable age total = price * quantity sets the total variable equal to the product of the values in the price and quantity variable
Arithmetic Expression	An expression involving arithmetic operators (+, -, *, /, %, **, //).	a + b, 3 * 4, 10 / 2, 2 ** 3
Comparison Expression	An expression that compares two values using operators (==, !=, >, <, >=, <=), and returns either True or False	a == b check the equivalency of a and b 5 > 3 will return True x != y checks if x is not equal to y, returning True if it is not
String Expression	An expression that manipulates strings with operators like + for concatenation or * for repetition.	"Hello" + " World", "a" * 3
Variable Reference	Referring to a variable in an expression to use its value.	x * 5 would return the value of x times 5 count - 1 would return the value of count minus 1
Compound Expression	A combination of multiple expressions into one, possibly using parentheses for grouping.	(a + b) * 3