Python programming

Question 1

From this code define:
a module
an instancevariable
a function
a method

import random
class Dice:
def __init__(self):
self.value = random.randint(1,6)

def roll(self):
self.value = random.randint(1,6)

def getValue(self):
return self.value

def __str__(self):
return ‘Dice = ‘ + self.value

t1 = Dice() print(t1.getValue())

Answer 1

A module from this code is random.

The instancevariable is the attribute which is self.value

a function is randint

a method is roll(), getvalue(). Methods are functions defined in a class.

Question 2

Define the datatypes of the following expressions:

4%3
1.0 * 7
5*7
4>3
‘12’ + ‘13’
[ e for e in range(7)]
[True, False, True]
‘1’ + ‘2’
{‘abc’: 4}
(‘x’, 4)

Answer 2

int
float
int
int
str
lst
lst
str
dict
tuple

Question 3

What is the word import in python?

Answer 3

A keyword.

“keywords” refer to reserved words that have special meanings and functions in the language.

If, while, else, def, return ect. are also keywords

Question 4

Give examples of built in functions in Python

Answer 4

print()
len()
input()

Question 5

What is the difference between tuples and lists?

Answer 5

tuples are unmutable and can contain different datatypes. Can be used to create dictionaries.

Question 6

What are boolean values?

Answer 6

True or False

Question 7

Difference between “/” “//”

Answer 7

/ gives result in float type
// integer division

Question 8

Difference between integer counting and float counting?

Answer 8

integer counting is exact while floating point counting can give rounding errors.

Question 9

What is true about the for loop?

• you can write for loops that does not stop
• You can have if statements in a for loop
• You can have if-statements in a for loop
• You can always replace a for loop with an if statement
• clauses in a for loop always have to run at least once
• With the word “continue” you leave a for loop

Answer 9

True
True
False
False
False

Question 10

True or false: If you know the index of a value in a list you can change it.

Answer 10

True

Question 11

Given the following code, what are the values of a and b to make print(y) give [9,8,3]?

x = [1, 2, 3]
y= [4, 5, 6]
y=x
x[a] = 9
y[b] = 8
print(y)

Answer 11

a = 0 because the first index in the list should be 9

b = 1 because the second index in the list should be 8.

Question 12

How can you recognize a class?

Answer 12

The first letter is capital

Question 13

What is slicing? what can you do with it?

Answer 13

manipulate lists.

You can create new lists with only parts of the old list.

Give the list (or parts of the list) in reverse.

Give a copy of the list

Question 14

Give example of functions that take strings as parameters

Answer 14

Input()
split()

Question 15

What is an argument and what is a parameter?

Answer 15

def g(a, b)
return a + b

x = 8
y = g(x, 14)

In this code a and b are parameters for the function g.

x and 14 are arguments passed to the function.