Chapter 2 Runestone Python

data types

integer, string, floating point

float

The Python data type that represents numbers with decimals

type conversion function

A function that can convert a data value from one type to another.

int

a Python data type that holds integers (positive and negative whole numbers plus zero)

variable

name that refers to a value

assignment statements

a statement that assigns a value to a variable name

assignment operator

= is Python's assignment token, which should not be confused with the mathematical comparison operator using the same symbol.

variable name

A name given to a variable. Variable names in Python consist of a sequence of letters (a..z, A..Z, and _) and digits (0..9) that begins with a letter. In best programming practice, variable names should be chosen so that they describe their use in the program, making the program self documenting.

keywords

A reserved word that is used by the compiler to parse a program. cannot be used as variable names

statement

instruction that the Python interpreter can execute

expression

A combination of variables, operators, and values that represents a single result value.

evaluates

interpreter does this to the expression and dsiplays the result

operands

One of the values on which an operator operates.

integer division

An operation that divides one integer by another and yields an integer. Integer division yields only the whole number of times that the numerator is divisible by the denominator and discards any remainder (always truncates)

modulus operator

An operator, denoted with a percent sign ( %), that works on integers and yields the remainder when one number is divided by another.

prompt string

Used during interactive input to provide the user with hints as to what type of value to enter.

Rules of Precedence / Order of Operations

PEMDAS -- exponent goes from right to left but everything else is left to right

initialize (a variable)

give a variable an initial value

increment

updating a variable by adding

decrement

updating a variable by subtracting

operator

A special symbol that represents a simple computation like addition, multiplication, or string concatenation.

str

A Python data type that holds a string of characters (or converts to string data type)

comment

# information in a program that is meant for programmers and has no effect on the execution of a program.