Module 1 Types and Expressions

Part 1

Data Types

Refers to the type of data a value representing

Numeric - All Numbers

• Integers, floating-point numbers, comple numbers

• Boolean values

Sequences - Ordered Collections

• lists, tuples, ranges

• strings (a sequence of characters)

Mappings - Key-Value collections

• dictionaries

Integeres

Whole numbers of any size

Floating-point Numbers (or float)

Any numeric value with decimal point will be read as a float data type

• precision up to 14 decimals places

Float Rounding

Include the value and the number of decimal places you wish to round

Banker’s Rounding or Round Half-to-Even

When you use the function to round to the nearest integer, it will always prefer the closes even integer

Complex

Numbers with a real and an imaginary part

• “j” as the imaginary unit

Boolean

This data type represents two values: True or False

• numeric

Strings

Considered a sequence, since a sequence of none, one, or more characters.

• represented by encolosing the value in single or double quotes.

Functions - len()

Return the number of charater; the length of the string

Function - replace()

Replaces part of the string with another string

Function - lower() & upper()

Changes the string to either allow all lower case or upper case

Function - isnumeric()

Checks if the string is a number

Function - split()

Useful function for splitting a string into separate parts

View of All Functions

Type

Type “type“ inside the parentheses to define any value. In return the funciton will give the data type of that value.

int()

This function converts any value you define in between the parentheses into an integer type.

float()

This function converts any value you define in between the parentheses into a float type.

str()

This function converts any value you define in between the parentheses into a string type.

String Formatting

The process of buildin a larger string value by combining or “glueing” strings and other values.

Concatenation

the operation of “gluing“ string values together

• “+”

• if you have a numeric type value it will perform addition

• cannot perform concatenation with a numeric value

f-string

Allows you to embed variables or expressions directly inside a string

• add the letter “f'“ as prefix

• any non string {}

f-string w/ Rounding and Fixing

• add a colon : after the float value you want to round

• add a period . followed by the number that will represent the decimal place you want to round

• add “f” to make it fixed

Escape Sequences

A special type of character that we can use to represent characters or formatting into a string

• “\”

Formatting Characters - Escape Sequences

\b: - backspace

\t: tab(indentation)

\n: new line

Escape Sequences - Characters

\”: double-quote

\’: single-quote

\\: backslash

Expressions

A combination of values, variables, and operators that your computer will calculate and evaluate into a value.

Literals

These are the simplest of expressions since they do not need evaluation since they are the values themselves.

Operators

Wheneber you use any sort of operators like mathematical operators, Python must resolve the value before is able to perform any other task.

Function Calls

Some function calls are expressions. Whenever you use a funciton, the computer must evluate the value it returns.

Comparion Operators

• in

• not in

• is

• is not

Logical Operators

• not

• and

• or