2: Variables, Expressions, Statements

Question 0

What is a type?

Answer 0

Each separate value can be categorized under one of these. Some of these categories include: integer (numbers), float (numbers with decimal points) and string (sequence of letters)

Note: strings must be contained by quotation marks.

Question 1

What is a value?

Answer 1

One of the basic things a program works with, such as a letter or a number.

Question 2

What does Python do with commas in large integers?

Answer 2

> > > print 1,000,000
100

Python interprets commas as a seperation between a sequence of integers, which it then prints with spaces in between.

Question 3

What is a variable?

Answer 3

A name that refers to a value.

Question 4

What is an assignment statement?

Answer 4

This creates new variables and gives them values.

EX of three various ________:

> > > message= “let’s do something”
N = 17
pi = 3.14159265

Question 5

What is a statement?

Answer 5

A unit of code that the Python interpreter can execute.

Question 6

What is an operator?

Answer 6

Special symbols that represent computations like addition and multiplication.

Question 7

What are operands?

Answer 7

The values the operator is applied to.

Question 8

What is floor division?

Answer 8

An operation that is performed between two integers this producing a third integer as the result.

Ex. 9/10 = 0
8/3 = 2

Question 9

What is floating point division?

Answer 9

A division function where at least one floating point number is involved, thus producing an answer as a float or number including a decimal point.

Ex. 59/60.0 = .98333333

Question 10

What is an expression?

Answer 10

A combination of values, variables, and operators. In addition, a value or a variable is considered an expression all by itself.

Question 11

What are the rules of precedence? Think of algebra.

Answer 11

PEMDAS

Parentheses
Exponentation
Multiplication or Division (left to right)
Addition or Subtraction (left to right)

Question 12

What is the modulus operator?

Answer 12

An equation that works on integers and yields the remainder when the first operands is divided by the second. In Python, the operator for this equation is %

> > > quotient = 7/3
print quotient
2

> > > remainder = 7%3
print remainder
1

Question 13

What is concatenation?

Answer 13

The joining of strings by linking them end to end.

> > > first = ‘100’
second = ‘150’
print first + second
100150

Question 14

raw_input

Answer 14

A built in function within Python which when the function is called, the program stops and waits for the user to type something.

Then, once the user presses return or enter, the program returns what the user typed as a string

> > > input = raw_input ()
Hi there computer
print input
Hi there computer

Question 15

/n

Answer 15

A prompt which represents a new line. It is a special character that causes a line break.

Question 16

#

Answer 16

A symbol which prompts Python to ignore anything added afterwards. This symbol is a way for programmers to add notes or comments to their program.

You can add comments on a line by itself or after your line of code. Everything from the # to the end of the line is ignored.

Question 17

‘Use before def’

Answer 17

Common bug: You are trying to use a variable before you have assigned it a value

Remember variables are case sensitive

Case does not = case