Basics of Python Programming in one PDF File.pdf

All the basics you need to start doing python. A beginner friendly document.

1. Python Basics
LECTURE 1

2. Python
▪a programming language that lets you work
quickly and integrate systems more effectively
(Python Software Foundation)
▪created by Guido van Rossum (1990)
▪named after the popular British comedy troupe
Monty Python’s Flying Circus
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova

3. Why Python?
▪works on different platforms (Windows, Mac, Linux,
Raspberry Pi, etc.)
▪has a simple syntax
▪runs on an interpreter system
▪can be treated in a procedural way, an object-
oriented way or a functional way
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova

4. Why Python?
▪has extremely rich libraries
▪has extensive online documentation
▪has multiple programming communities
▪has diverse applications:
✓web development (server-side)
✓software development
✓mathematics
✓system scripting
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova

5. Python Input/Output Functions
print()
▪used to generate an output at the console
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
print("Hello, Class!")
print(1)

6. Python Input/Output Functions
input()
▪used to read a line of input entered by the user at
the console and returns it as a string
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
num = input("Enter number:")
print(num)

7. Python Syntax
▪indentation
•refers to the spaces at the beginning of a code line
•very important in Python since it indicates a block
of code
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
if2>1:
print("Two is greater than one.")
if2>1:
print("Two is greater than one.")

8. Python Syntax
▪indentation
•number of spaces is up to you as a programmer
•the most common use is four, but it has to be at
least one
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
if2>1:
print("Two is greater than one.")
if2>1:
print("Two is greater than one.")

9. Python Syntax
▪indentation
•the same number of spaces should be used in the
same block of code
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
if2>1:
print("Two is greater than one!")
print("Two is greater than one!")
if2>1:
print("Two is greater than one!")
print("Two is greater than one!")

10. Python Comments
▪start with a #
▪make code readable
▪completely ignored by the interpreter
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
#This is a comment.
print("Hello, Class!")
print("Hello, Class!") #This is a comment.

11. Python Comments
▪Multiline Comments
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
#Comment1
#Comment2
#Comment3
print("Hello, Class!")
"""Comment1
Comment2
Comment3"""
print("Hello, Class!")
Multiline String can also be used
•since Python will ignore string literals
that are not assigned to a variable

12. Python Variables
▪containers for storing data values
▪Python has no command for declaring a variable
▪a variable is created the moment you first assign a value to it
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
x = 1
y = "Hello"
print(x)
print(y)
assignment operator: =
a, b, c = 9, 2.5, 'Hello'
print(a)
print(b)
print(c)
num1 = num2 = 20
print(num1)
print(num2)

13. Python Variables
Rules for naming variables
▪must start with a letter or the underscore character
▪cannot start with a number
▪can only contain alpha-numeric characters and underscores (A-
z, 0-9, and _ )
▪are case-sensitive (age, Age and AGE are three different
variables)
▪cannot be any of the Python keywords
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova

14. Python Variables
▪do not need to be declared with any particular type,
and can even change type after they have been set
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
x = 1 # x is of type int
x = "Hello" # x is now of type str
print(x)

15. Python Variables
▪Casting
▪done to specify type of
variable
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
x = str(1) # x will be '1'
y = int(1) # y will be 1
z = float(1) # z will be 1.0
▪type() function
▪returns the data type of a
variable
▪Ex:
x = 1
y = "Hello"
print(type(x))
print(type(y))

16. Python Variables
output variables
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
x = "A good day"
print(x)
x = "A"
y = "good"
z = "day"
print(x, y, z)
x = "A"
y = "good"
z = "day"
print(x+y+z)
x = 2
y = 9
print(x+y)
x = 2
y = "good"
print(x+y)
x = 2
y = "good"
print(x,y)

17. Python Variables
Global variables
▪created outside of a function
▪can be used inside and outside of functions
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
x = "hi"
def myfunc():
print("Python is " + x)
myfunc()
x = "hi"
def myfunc():
x = "hello"
print("Python is " + x)
myfunc()
print("Python is " + x)

18. Python Data Types
Built-in Data Types
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
Type
Text Type: str
Numeric Types: int,float,complex
Sequence Types: list,tuple,range
Mapping Type: dict
Set Types: set,frozenset
Boolean Type: bool
Binary Types: bytes,bytearray,memoryview
None Type: NoneType

19. Python Data Types
Python Numbers
▪integer (int), floating point number (float), complex
✓int–whole number (positive/negative)
✓float–contains decimal (positive/negative); can also be scientific
numbers with an “e” to indicate power of 10
✓complex–written with a “j” as the imaginary part
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova

20. Python Data Types
Python Numbers
▪integer (int), floating point number (float), complex
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
x = 1 # int
y1 = 2.9 # float
y2 = 3e4 # float
z = 5j# complex
print(type(x))
print(type(y1))
print(type(y2))
print(type(z))
to verify the data type:

21. Python Data Types
Python Strings
▪Strings –enclosed by "" or ''
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
x = "Hello" # string
y = 'Hello' # string
x = """Python is a programming
language that lets you work quickly
and integrate systems more
effectively."""
print(x)
Multiline String
•enclosed with three (3) double or
single quotes

22. Python Data Types
Python Booleans
▪Trueor False
▪usually used in evaluating expressions
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
print(3>2)
print(3<2)
print(3==2)

23. Python Data Types
Python Booleans
▪bool() function
▪evaluates any value to true or false
▪if a value has content, it is evaluated to true(i.e. any string is true except empty string,
any number is true except 0, etc.)
▪empty values, such as (),[],{},"",0,and None, evaluate to false
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
bool("a") #true
bool("1") #true
bool('') #false
bool(None) #false

24. Python Data Types
Lists
▪used to store multiple items in a single variable
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
colorList = ["red", "blue", "yellow", "green"]
print(colorList)
✓Items in a list are ordered, changeable, and
allow duplicate values
✓They are indexed (1
st
item has index [0], the 2
nd
item has index [1], and so on)
enclosed with
brackets

25. Python Data Types
Lists
▪can be of any data type
▪can contain different data types
▪defined as objects with the data type 'list'
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
list1 = ["red", "blue", "yellow"]
list2 = [1, 3, 5, 7, 9]
list3 = [False, True, False]
list1 = ["Peter", 30, "male", True, "Mary", 29, "female"]

26. Python Data Types
Lists
▪len() function
▪determines the number of items in a list
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
colorList = ["red", "blue", "yellow", "green"]
print(len(colorList))

27. Python Data Types
Lists
▪list() Constructor
▪can also be used to create a new list
▪Ex:
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
colorList = list(("red", "blue", "yellow", "green"))
print(len(colorList))
double
parentheses

28. Python Data Types
Python Collections (Arrays)
▪4collection data types:
1.List
▪a collection which is ordered, changeable, and allows duplicate members
2.Tuple
▪a collection which is ordered, unchangeable, and allows duplicate members.
3.Set
▪a collection which is unordered, unchangeable (but you can add/remove items), and unindexed.
No duplicate members.
4.Dictionary
▪a collection which is ordered** and changeable. No duplicate members.
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova

29. Python Arithmetic Operators
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
Operator Name Example
+ Addition x+y
- Subtraction x-y
* Multiplication x*y
/ Division x/y
% Modulus x%y
** Exponentiation x**y
// Floor division x//y

30. Python Comparison Operators
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
Operator Name Example
== Equal x == y
!= Not equal x != y
> Greater than x > y
< Less than x < y
>= Greater than or equal tox >= y
<= Less than or equal tox <= y

31. Python Logical Operators
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
Operator Name Example
and returns True if both statements are
true
x < 1 andx < 5
or returns True if one of the statements
is true
x < 4 or x < 8
not reverse the result, returns False if the
result is true
not(x < 3 and x < 6)

32. Python Identity Operators
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
Operator Name Example
is Returns True if both variables are the
same object
x is y
is notReturns True if both variables are not
the same object
x is not y

33. Python Membership Operators
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
Operator Name Example
in Returns True if a value is present in a
sequence
x in y
not in Returns True if a value is not present
in a sequence
x not in y

34. Python Bitwise Operators
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
Operator Name Description Example
& AND Sets each bit to 1 if both bits are 1x & y
| OR Sets each bit to 1 if one of two bits is 1x | y
^ XOR Sets each bit to 1 if only one of two bits is 1x ^ y
~ NOT Inverts all the bits ~x
<< Zero fill left shiftShift left by pushing zeros in from the right
and let the leftmost bits fall off
x << 2
>> Signed right shiftShift right by pushing copies of the leftmost
bit in from the left, and let the rightmost bits
fall off
x >> 2
& AND Sets each bit to 1 if both bits are 1x & y

35. Operator
Precedence
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova
Operator Name
() Parentheses
** Exponentiation
+x-x~x Unary plus, unary minus, and bitwise NOT
*///% Multiplication, division, floor division, and modulus
+- Addition and subtraction
<<>> Bitwise left and right shifts
& Bitwise AND
^ Bitwise XOR
| Bitwise OR
==,!=,>,>=,<,<=,
is, is not,in,not in
Comparisons, identity, and membership operators
not Logical NOT
and AND
or OR
If two operators have
the same precedence,
the expression is
evaluated from left
to right.

36. References:
W3schools (Python Tutorial)
Programiz
ECE115.2: Object Oriented Programming for ECE Prepared by: Engr. Ria Marie P. Cordova