Introduction to Python lab

advertisement
College of Engineering and Technology
Name: Karabo Davis Bogaisang
Student ID: 14001009
LAB EXPERIMENT: LAB 01, Introduction to Python
Module: Artificial Intelligence and Neural Networks
Code: EEEN 519
Introduction
Python is a general-purpose interpreted, interactive, object-oriented, and high-level programming
language. It was created by Guido van Rossum during 1985-1990. It uses English keywords frequently
where as other languages use punctuation, and it has fewer syntactical constructions than other
languages.
Objectives
• Introducticing basic mathematical operations, variable types and printing options.
◦ Modules
◦ comments
◦ print
◦ arithmetic operators
◦ if
◦ else
◦ elif
◦ loops
◦ for
◦ while
◦ break
◦ continue
Background
Variables are nothing but reserved memory locations to store values. This means that when you create a
variable you reserve some space in memory.
The data stored in memory can be of many types. For example, a person's age is stored as a numeric
value and his or her address is stored as alphanumeric characters. Python has various standard data
types that are used to define the operations possible on them and the storage method for each of them.
Python has five standard data types:
•
•
•
•
•
Numbers
String
List
Tuple
Dictionary
Lists are the most versatile of Python's compound data types. A list contains items separated by
commas and enclosed within square brackets ([]). To some extent, lists are similar to arrays in C. One
difference between them is that all the items belonging to a list can be of different data type.
A tuple is another sequence data type that is similar to the list. A tuple consists of a number of values
separated by commas. Unlike lists, however, tuples are enclosed within parentheses.
The main differences between lists and tuples are: Lists are enclosed in brackets ( [ ] ) and their
elements and size can be changed, while tuples are enclosed in parentheses ( ( ) ) and cannot be
updated. Tuples can be thought of as read-only lists
Python's dictionaries are kind of hash table type. They work like associative arrays or hashes found in
Perl and consist of key-value pairs. A dictionary key can be almost any Python type, but are usually
numbers or strings. Values, on the other hand, can be any arbitrary Python object.
Dictionaries are enclosed by curly braces ({ }) and values can be assigned and accessed using square
braces ([]).
Decision making is anticipation of conditions occurring while execution of the program and specifying
actions taken according to the conditions.
Decision structures evaluate multiple expressions which produce TRUE or FALSE as outcome. You
need to determine which action to take and which statements to execute if outcome is TRUE or FALSE
otherwise.
In general, statements are executed sequentially: The first statement in a function is executed first,
followed by the second, and so on. There may be a situation when you need to execute a block of code
several number of times.
Programming languages provide various control structures that allow for more complicated execution
paths.
A loop statement allows us to execute a statement or group of statements multiple times.
Experiment
# LAB 01
# 1.0 VARIABLES
import random
a = 5
b = 13
x = 5.0
y = 13.0
m = "Mary"
n = "Nancy"
print(a)
print(a, x, m, n)
print(a + b)
c = a + b
print(c)
c = 20 + a
print(c)
# 1.2 MANIPULATING NUMBERS
print("5 + 2 =", 5+2)
print("5 - 2 =", 5-2)
print("5 * 2 =", 5*2)
print("5 / 2 =", 5/2)
print("5 % 2 =", 5%2)
print("5 ** 2 =", 5**2)
print("5 // 2 =", 5//2)
print("1 + 2 - 3 * 2 =", 1 + 2 - 3 * 2)
print("(1 + 2 - 3) * 2 =", (1 + 2 - 3) * 2)
# 2.0 MAKING COMMENTS
# This is my first Python program
print("Hello World!")
# This is my second Python program
print("Hello World!")
print("""
Look at the odd formatting of
these
They will show up as defined!
""")
quote = "\"Always remember your unique,"
multi_line_quote = ''' just like everyone else" '''
print(quote + multi_line_quote)
# embed string in output
print("%s %s %s" % ('I like the quote', quote, multi_line_quote))
# printing new line
print("I don't like ", end="")
print("newlines")
# printing string multiple times
print('\n' * 5)
# 3.0 LISTS
# creating a list
grocery_list = ['Juice', 'Tomatoes', 'Potatoes', 'Bananas']
print('The first item is', grocery_list[1])
# change the value in a list
grocery_list[0] = "Green Juice"
print(grocery_list)
# subset a list
print(grocery_list[1:3])
# add values
grocery_list.append('Onions')
print(grocery_list)
# insert item
grocery_list.insert(1, "Pickle")
print(grocery_list)
# delete item
del grocery_list[4]
print(grocery_list)
# 4.0 TUPLES
pi_tuple = (3, 1, 4, 1, 5, 9)
print(pi_tuple)
# Convert tuple into a list
new_tuple = list(pi_tuple)
print(new_tuple)
# Convert a list into a tuple
new_list = tuple(grocery_list)
print(new_list)
# 5.0 DICTIONARY OR MAP
super_villains = {'Fiddler': 'Isaac Bowin', 'Captain Cold': 'Leonard Snart', 'Weather
Wizard': 'Mark Mardon', 'Mirror Master': 'Sam Scudder', 'Pied Piper': 'Thomas Peterson'}
print(super_villains['Captain Cold'])
# number of items in a map
print(len(super_villains))
# value of the passed key
print(super_villains.get("Pied Piper"))
# list of dictionary keys
print(super_villains.keys())
# list of dictionary values
print(super_villains.values())
# 6.0 CONDITIONALS
age = 30
if age > 16:
print('You are
if age > 16:
print('You are
else:
print('You are
if age >= 21:
print('You are
elif age >= 16:
print('You are
else:
print('You are
#
old enough to drive')
old enough to drive')
not old enough to drive')
old enough to drive a tractor trailer')
old enough to drive a car')
not old enough to drive')
# 7.0 LOOPS
for x in range(0, 10):
print(x , ' ', end="")
print('\n')
for y in grocery_list:
print(y)
for x in [2, 4, 6, 8, 10]:
print(x)
num_list = [[1, 2, 3], [10, 20, 30], [100, 200, 300]];
for x in range(0, 3):
for y in range(0, 3):
print(num_list[x][y])
# 8.0 WHILE LOOPS
random_num = random.randrange(0, 100)
while (random_num != 15):
print(random_num)
random_num = random.randrange(0, 100)
i = 0;
while (i <= 20):
if i%2 == 0:
print(i)
elif i == 9:
# Force the loop to end all together
break
else:
# Shorthand for i = i + 1
i += 1
# Skips to the next iteration of the loop
continue
i += 1
Results
Print outs obtained after running the codes.
1.0 VARIABLES
5
5 5.0 Mary Nancy
18
18
25
1.2 MANIPULATING NUMBERS
5+2=7
5-2=3
5 * 2 = 10
5 / 2 = 2.5
5%2=1
5 ** 2 = 25
5 // 2 = 2
1 + 2 - 3 * 2 = -3
(1 + 2 - 3) * 2 = 0
2.0 MAKING COMMENTS
Hello World!
Hello World!
Look at the odd formatting of
these
They will show up as defined!
"Always remember your unique, just like everyone else"
I like the quote "Always remember your unique, just like everyone else"
I don't like newlines
3.0 LISTS
The first item is Tomatoes
['Green Juice', 'Tomatoes', 'Potatoes', 'Bananas']
['Tomatoes', 'Potatoes']
['Green Juice', 'Tomatoes', 'Potatoes', 'Bananas', 'Onions']
['Green Juice', 'Pickle', 'Tomatoes', 'Potatoes', 'Bananas', 'Onions']
['Green Juice', 'Pickle', 'Tomatoes', 'Potatoes', 'Onions']
4.0 TUPLES
(3, 1, 4, 1, 5, 9)
[3, 1, 4, 1, 5, 9]
('Tomatoes', 'Pickle', 'Onions', 'Green Juice')
5.0 DICTIONARY OR MAP
Leonard Snart
5
Thomas Peterson
dict_keys(['Fiddler', 'Captain Cold', 'Weather Wizard', 'Mirror Master', 'Pied Piper'])
dict_values(['Isaac Bowin', 'Leonard Snart', 'Mark Mardon', 'Sam Scudder', 'Thomas Peterson'])
6.0 CONDITIONALS
You are old enough to drive
You are old enough to drive
You are old enough to drive a tractor trailer
7.0 FOR LOOPS
0 1 2 3 4 5 6 7 8 9
Tomatoes
Pickle
Onions
Green Juice
2
4
6
8
10
1
2
3
10
20
30
100
200
300
8.0 WHILE LOOPS
85
97
62
25
75
24
41
69
42
27
45
46
6
59
73
14
80
85
35
76
81
69
94
96
7
59
22
48
7
1
24
40
9
9
8
92
48
79
46
17
58
35
51
28
36
78
68
37
98
86
96
33
91
88
20
23
59
66
85
23
91
14
11
97
61
89
45
47
59
31
50
84
21
26
55
2
77
23
55
1
29
96
68
24
76
43
12
67
52
0
2
4
6
8
Questions and Solutions
Q 3.1: Remove ‘Potatoes’ from the grocery list?
del grocery_list[3]
print(grocery_list)
['Green Juice', 'Pickle', 'Tomatoes', 'Onions']
Q 3.2:Sort the list?
grocery_list.sort()
print(grocery_list)
['Green Juice', 'Onions', 'Pickle', 'Tomatoes']
Q 3.3:Reverse sort the list?
grocery_list.reverse()
print(grocery_list)
['Tomatoes', 'Pickle', 'Onions', 'Green Juice']
Q 4.1: Convert grocery list into a tuple?
new_grocery_list = tuple(grocery_list)
print(new_grocery_list)
('Tomatoes', 'Pickle', 'Onions', 'Green Juice')
Q 5.1: Delete Fiddler entry together with its value?
del super_villains["Fiddler"]
print(super_villains)
{'Captain Cold': 'Leonard Snart', 'Weather Wizard': 'Mark Mardon', 'Mirror Master': 'Sam Scudder',
'Pied Piper': 'Thomas Peterson'}
Q 5.2: Replace a value at 'Pied Piper' with 'Hartley Rathaway'
super_villains["Pied Piper"] = "Rathaway"
print(super_villains)
{'Captain Cold': 'Leonard Snart', 'Weather Wizard': 'Mark Mardon', 'Mirror Master': 'Sam Scudder',
'Pied Piper': 'Rathaway'}
Q 6.1: Write the following code: if you are 1 or 18 or between the ages of 1 and 18, then
you get a birthday party. Else if you are 21 or 65 or greater than 65, then you get a birthday party
with your family. Else if you are not 30 years of age, then you don’t get a birthday party. Else
you get a birthday party yeah.
if age >= 1 and age <= 18:
print('You get a birthday party')
elif age == 21 or age >= 65:
print('You get a birthday with a family')
elif age != 30:
print('You do not get a birthday party')
else:
print('You get a birthday party yeah')
You get a birthday party yeah
Q 7.1: Change the following Python code from using a
while loop to for loop:
x=1
while x<10:
print x,
x+=1
for x in range (1, 10):
print(x)
1
2
3
4
5
6
7
8
9
Q 7.2: Change the following Python code from a for loop
to a while loop:
for i in range(1,50):
print i,
i = 1
while i < 50:
print(i)
i += 1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Conclusion
Basic mathematical operations were covered. Operations from variable types, printing options,
comments, arithmetic operators, order of operation, lists, tuples, dictionaries, conditional operators,
logical operators, if, else, elif, loops, for, while, break and continue. The objectives of the experiment
were meet.
Reference
https://www.tutorialspoint.com/python
Download